前言

本文章只是单纯记录课堂老师布置的课堂作业代码，题目都比较简单，所以没有写解题思路，相信大家都能理解，当然其中有的解法和代码不是最优的，当时只是为了完成题目，后来也懒得改了，如果有不恰当或者不正确的地方，欢迎指出

备注：有的忘记记录题目信息了，有的题目直接在作业系统里面提交了，请见谅，将就着看吧

1、

查看代码 
package java_works;

import java.util.Scanner;

public class java_10001 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc=new Scanner(System.in);

		String b=sc.nextLine();

		int zm=0,kg=0,qt=0;

		for(int i=0;i<b.length();i++)

		{

			if(b.charAt(i)>=65&&b.charAt(i)<=90)

				zm++;

			else if(b.charAt(i)>=97&&b.charAt(i)<=122)

				zm++;

			else if(b.charAt(i)==32)

				kg++;

			else

				qt++;

		}

		System.out.println("字母:"+zm);

		System.out.println("空格:"+kg);

		System.out.println("其他:"+qt);

	}

}

2、

查看代码 
package java_works;

import java.text.DecimalFormat;

import java.util.Scanner;

public class java_10002 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc=new Scanner(System.in);

		int k=sc.nextInt();

		double sum=0;

		for(double i=0;i<=k;i++)

		{

			sum=sum+((i+6)/(i+10));

		}

		System.out.print("sum:");

		System.out.printf("%.5f",sum);

	}

}

3、输入正整数N，输出[1, N]的之间的质数

查看代码 
package java_works;

import java.util.Scanner;

public class java_10003 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc=new Scanner(System.in);

		int N=-1;

		N=sc.nextInt();

		for(int i=2;i<=N;i++)

		{

			int j;

			for(j=2;j<=Math.sqrt(i);j++)

			{

				if(i%j==0)break;

			}

			if(j>Math.sqrt(i))

				System.out.print(i+" ");

		}

	}

}

4、用户输入正整数K为3-6之间的数，然后输出k位数的水仙花数

查看代码 
package java_works;

import java.util.Scanner;

public class java_10004 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		while(true) {

			Scanner sc=new Scanner(System.in);

			int K=-1;

			K=sc.nextInt();

			if(K == 0)

			{

				break;

			}

			int a[] = new int[K];

			int num = (int) Math.pow(10, K - 1) + 1;

			while (num <= Math.pow(10, K)) {

	            int sum = 0;

	            for (int j = 0; j < K; j++)

	                a[j] = (int) (num / Math.pow(10, j) % 10);

	            for (int j = 0; j < K; j++)

	                sum = sum + (int) Math.pow(a[j],K);

	            if (num == sum)

	                System.out.print(num + " ");

	            num++;

	        }

		}

	}

}

5、输入正整数K，用二维数组生成并存储K阶方阵，第一行为: 1, 2, 3, ..., K, 第二行为: K+1, K+2, ... ,K+K, ... 依次类推；然后输出方阵的转置。

查看代码 
package java_works;

import java.util.Scanner;

public class java_10005 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int K = sc.nextInt();

		int a[][] = new int[K][K];

		int b[][] = new int[K][K];

		int z=1;

		for(int i=0;i<K;i++)

		{

			for(int j=0;j<K;j++)

			{

				a[i][j]=z;

				z++;

			}

		}

		for(int i=0;i<K;i++)

		{

			for(int j=0;j<K;j++)

			{

				b[j][i]=a[i][j];

			}

		}

		for(int i=0;i<K;i++)

		{

			for(int j=0;j<K;j++)

			{

				System.out.print(b[i][j]+" ");

			}

			System.out.println();

		}

	}

}

6、输入正整数N，然后输入N个浮点数，然后计算并输出它们平均值和方差。

查看代码 
package java_works;

import java.util.Scanner;

public class java_10006 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = sc.nextInt();

		double[] a = new double[N];

		for(int i=0;i<a.length;i++)

		{

			a[i]=sc.nextDouble();

		}

		Double sum=0.0;

		for(int i=0;i<a.length;i++)

		{

			sum=sum+a[i];                   //求和

		}

		double mean = 0.0,diff=0.0;

		mean = sum / N;

		double c=0.0;

		for(int i=0;i<a.length;i++)

		{

			c=c+Math.pow((a[i]-mean),2);

		}

		diff=c/N;

		System.out.printf("mean:"+"%.5f",mean);

		System.out.println();

		System.out.printf("diff:"+"%.5f",diff);

	}

}

7、输入正整数N，然后输入N个浮点数，然后计算并输出它们最小值和最大值。

查看代码 
package java_works;

import java.util.Scanner;

public class java_10007 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = sc.nextInt();

		Double[] a = new Double[N];

		for(int i=0;i<N;i++)

		{

			a[i]=sc.nextDouble();

		}

		double minv = a[0],maxv=a[0];

		for(int i=0;i<a.length;i++)

		{

			if(a[i]<minv)

				minv=a[i];

			if(a[i]>maxv)

				maxv=a[i];

		}

		System.out.printf("minv:"+"%.5f",minv);

		System.out.println();

		System.out.printf("maxv:"+"%.5f",maxv);

	}

}

8、输入正整数N，然后输入N个浮点数，再按从小到大排序并输出排序结果。

查看代码 
package java_works;

import java.util.Scanner;

public class java_10008 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = sc.nextInt();

		double[] a = new double[N];

		for(int i=0;i<a.length;i++)

		{

			a[i] = sc.nextDouble();

		}

		for(int i=0;i<a.length;i++)

			for(int j=0;j<a.length-1;j++)

			{

				double temp;

				if(a[j]>a[j+1])

				{

					temp=a[j+1];

					a[j+1]=a[j];

					a[j]=temp;

				}

			}

		for(int i=0;i<a.length;i++)

		{

			System.out.printf("%.5f\n",a[i]);

		}

	}

}

9、输入一行字符串，然后将每个单词的首字母变为大写

查看代码 
package java_works;

import java.util.Scanner;

public class java_10009 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str ;

		str = sc.nextLine();

		daxie(str);

	}

	public static void daxie(String s){

		String a[] = s.split(" ");

		for(int i=0;i<a.length;i++)

		{

			String s1=a[i].substring(0,1).toUpperCase()+a[i].substring(1);

			System.out.print(s1+" ");

		}

	}

}

10、从键盘输入一行字符串，请在单词间做逆序调整。举例：“cat loves dog”逆序成“dog loves cat”。

查看代码 
package java_works;

import java.util.Scanner;

public class Java_10010 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str;

		str = sc.nextLine();

		nixu(str);

	}

	public static void nixu(String s) {

		String[] a = s.split(" ");

		String temp = "";

		for (int i = 0; i < a.length/2; i++) {

			temp = a[i];

			a[i] = a[a.length-1-i];

			a[a.length-1-i] = temp;

		}

		for(int i=0;i<a.length;i++){

			System.out.print(a[i]+" ");

		}

	}

}

11、间隔符规范化。输入一行字符串，该字符串使用空格作为单词、符号等之间的间隔符。然而由于用户操作的问题，在录入间隔符时，可能输入了多个空格，现要求对输入的字符串进行处理，清除字符串的首尾空格，并且确保字符串中的间隔符只能有一个空格

查看代码 
package java_works;

import java.util.Scanner;

public class java_10011 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str = sc.nextLine();

		guiFanhua(str);

	}

	public static void guiFanhua(String s) {

		s=s.trim();                      //去除字符串首尾空格字符

		StringBuffer sb = new StringBuffer();

		int flag;

		for(int i=0;i<s.length();i++)

		{

			flag = 0;

			if(s.charAt(i)!=' ')

				sb.append(s.charAt(i));

			else {

				flag = 1;

			}try {

				if(s.charAt(i)==' '&&s.charAt(i+1)!=' ') {

					sb.append(' ');

				}

			}catch(Exception e) {

				continue;

			}

		}

		System.out.println(sb);

	}

}

12、输入M和N，然后计算一个球从M米高度自由下落，每次落地后反跳回原高度的一半，再落下，再反弹。计算它在第N次落地时共经过多少米？第N次落地时反弹多高

查看代码 
package java_works;

import java.util.Scanner;

public class java_10012 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int M = sc.nextInt();

		int N = sc.nextInt();

		Solve(M,N);

	}

	public static void Solve(int a,int b) {

		double L = 0.0,H = 0.0;

		for(int i=1;i<b;i++)

		{

			L=L+a/(Math.pow(2, i-1));

		}

		H=a/(Math.pow(2,b));

		System.out.printf("%.5f\n",L+a);

		System.out.printf("%.5f",H);

	}

}

13、输入正整数N，用1,2,3,..,N数字给N个学生编号，N个学生围成一圈。然后从第1个人开始报数（从 1 到 5 报数），凡报到 5的人退出圈子，问最后留下的是原来第几号的那位？

查看代码 
package java_works;

import java.util.Scanner;

public class java_10013 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = sc.nextInt();

		Solves(N);

	}

	public static void Solves(int a) {

		int[] b = new int[a];

		for(int i=0;i<a;i++)

		{

			b[i]=i+1;

		}

		int currentNum = 1;

		int count = b.length;

		for(int i=0;;i++)

		{

			if(count==1) {

				break;

			}

			if(i>=b.length) {

				i=0;

			}

			if(b[i]==0) {

				continue;

			}

			if(currentNum % 5 == 0) {

				count--;

				b[i]=0;

			}

			if(currentNum == 5) {

				currentNum = 1;

			}

			else {

				currentNum++;

			}

		}

		for(int i=0;i<b.length;i++)

		{

			if(b[i]!=0) {

				System.out.println(b[i]);

			}

		}

	}

}

14、输入某年某月某日，输出这一天是这一年的第几天。要特别注意闰年的判断，并且处理好闰年的情况输入一行字符串，统计并输出字符串中每个字符出现的次数

查看代码 
package java_works;

import java.util.Scanner;

import java.util.GregorianCalendar;

public class java_10014 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int year = 0,month = 0, day = 0;

		year = sc.nextInt();

		month = sc.nextInt();

		day = sc.nextInt();

		Solves(year,month,day);

	}

	public static void Solves(int n,int y,int r) {

		GregorianCalendar gre = new GregorianCalendar();//判断是否为闰年的方法

		boolean isLeapYear = gre.isLeapYear(n);//返回值是true，说明是润年，若返回值是false，则不是闰年

		int ap = isLeapYear?29:28;//判断2月份的天数

		int days=0;

		switch(y) {

		case 1:

			days=r;

			break;

		case 2:

			days=31+r;

			break;

		case 3:

			days=31+ap+r;

			break;

		case 4:

			days=31+ap+31+r;

			break;

		case 5:

			days=31+ap+31+30+r;

			break;

		case 6:

			days=31+ap+31+30+31+r;

			break;

		case 7:

			days=31+ap+31+30+31+30+r;

			break;

		case 8:

			days=31+ap+31+30+31+30+31+r;

			break;

		case 9:

			days=31+ap+31+30+31+30+31+31+r;

			break;

		case 10:

			days=31+ap+31+30+31+30+31+31+30+r;

			break;

		case 11:

			days=31+ap+31+30+31+30+31+31+30+31+r;

			default:

				days=31+ap+31+30+31+30+31+31+30+31+30+r;

		}

		System.out.println(days);

	}

}

15、输入一行字符串，统计并输出字符串中每个字符出现的次数

查看代码 
package java_works;

import java.util.Iterator;

import java.util.Scanner;

import java.util.TreeMap;

import java.util.Set;

public class java_10015 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str = sc.nextLine();

		char[] ch = str.toCharArray();

		method(ch);

		int blank = 0;

		for(int i=0;i<ch.length;i++)

		{

			if(ch[i]==' ')

				blank++;

		}

		System.out.println("空格:"+blank);

	}

	public static void method(char[] array) {

		//初始化一个长度为26的整型数组，初始值全为0，记录字符串中各个字符出现的次数

		int[] temp = new int[26];

		for(int i=0;i<temp.length;i++)

		{

			temp[i]=0;

		}

		//遍历字符数组，将其值对应的ASCII值作为整型数组下标

		for(int i=0;i<array.length;i++)

		{

			if(array[i]>='a'&&array[i]<='z')

			{

				temp[array[i]-'a']++;

			}

		}

		//打印输出每个小写英文字母及出现的次数

		for(int i=0;i<temp.length;i++)

		{

			System.out.println((char)(i+'a')+":"+temp[i]);

		}

	}

}

16、输入一行字符串，输出最先出现重复的字符

查看代码 
package java_works;

import java.util.Scanner;

public class java_10016 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str = sc.nextLine();

		getFirstIndex(str);

	}

	public static void getFirstIndex(String s) {

		String[] a = s.split("");

		for(int i=0;i<a.length;i++) {

			int num = 0;

			int index = 0;

			while(index<=i) {

				if(a[index].equals(a[i])) {

					num++;

				}

				index++;

			}

			if(num>1) {

				System.out.println(a[i]);

				break;

			}

		}

	}

}

17、输入一个正整数N，对它进行质因数分解并输出结果。例如：输入 90，打印出 90=2*3*3*5

查看代码 
package java_works;

import java.util.Scanner;

public class java_10017 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = sc.nextInt();

		Solve(N);

	}

	public static void Solve(int a) {

		System.out.print(a+"=");

		for(int i=2;i<a+1;i++) {

			while(a%i==0&&a!=i) {

				a/=i;

				System.out.print(i+"*");

			}

			if(a==i) {

				System.out.println(i);

				break;

			}

		}

	}

}

18、输入一个正整数N，输出[1, N]之间的“完数”。“完数”就是如果这个数恰好等于它的因子之和，则这个数就称为"完数"，例如6=1＋2＋3

查看代码 
package java_works;

import java.util.Scanner;

public class java_10018 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = sc.nextInt();

		Solve(N);

	}

	public static void Solve(int a) {

		for(int i=1;i<a;i++)

		{

			int sum = 0;

			for(int j=1;j<=i/2;j++)

			{

				if(i % j == 0)

				{

					sum+=j;

				}

			}

			if(sum == i)

			{

				System.out.print(i+" ");

			}

		}

	}

}

19、输入一行字符串，按照规格压缩，输出压缩后的字符串。压缩规格为：相同字符连续，则压缩为“字符+数字个数”，如"iamaaaaaAbcCCdD压缩为"iama5AbcC2dD"。

查看代码 
package java_works;

import java.util.Scanner;

public class java_10019 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str = sc.nextLine();

		compressStr(str);

	}

	public static void compressStr(String s) {

		StringBuilder sb = new StringBuilder();

		int count = 1;

		char c1=s.charAt(0);

		for(int i=1;i<s.length();i++)

		{

			char c2 = s.charAt(i);

			if(c1 == c2) {

				count++;

				continue;

			}

			if(count>1) {

				sb.append(c1).append(count);

			}else {

				sb.append(c1);

			}

			c1 = c2;

			count = 1;

		}

		if(count >1) {

			sb.append(c1).append(count);

		}else {

			sb.append(c1);

		}

		System.out.println(sb.toString());

	}

}

20、指令分割。输入正整数N，然后输入N行字符串，每一行字符串为一条指令。

查看代码 
package java_works;

import java.util.Scanner;

public class java_10020 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = -1;

		N = Integer.parseInt(sc.nextLine());

		String[] a = new String[N];

		for(int i=0;i<N;i++)

		{

			a[i] = sc.nextLine().replace(" ","");

		}

		sc.close();

		String[] singleArr = {"printi","jg","jl","je","jne","jmp"};

		String[] doubleArr = {"mov","add","sub","mul","div","cmp"};

		for(int i=0;i<N;i++) {

			int flag = 0;

			for(String tmp:singleArr)

			{

				if(a[i].indexOf(":"+tmp)>0)

				{

					flag = 1;

					String[] tmpStrArr = a[i].split(":"+tmp);

					System.out.println("LineNo="+tmpStrArr[0]);

					System.out.println("OP="+tmp);

					System.out.println("N1="+tmpStrArr[1]);

				}

			}

			if(flag == 0){

				for(String tmp:doubleArr)

				{

					if(a[i].indexOf(":"+tmp)>0) {

						flag = 2;

						String[] tmpStrArr = a[i].split(":"+tmp);

						System.out.println("LineNo="+tmpStrArr[0]);

						System.out.println("OP="+tmp);

						System.out.println("N1="+tmpStrArr[1].split(",")[0]);

						System.out.println("N2="+tmpStrArr[1].split(",")[1]);

					}

				}

			}

			if(flag == 0)

				return;

		}

	}

}

21、二进制指令序列解码成字符串源代码。输入一行字符串，输入的字符串为二进制指令序列的16进制形式字符串

22、抱歉，忘记写了，题目也给忘了，索性摆烂。。。

23、输入正整数N，然后输入N*N个正整数按一行一行的顺序排列成N行N列的矩阵，要求对矩阵按垂直方向翻转，并输出结果

查看代码 
import java.util.Scanner;

public class java_10023 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int[][] a = new int[N][N];

		for(int i = 0;i < N; i++)

			for(int j = 0;j < N;j++)

			{

				a[i][j] = sc.nextInt();

			}

 		//实现垂直翻转矩阵

		for(int i = N - 1;i > -1;i--)

 		{

 			for(int j = 0;j < N;j++)

 			{

 				System.out.print(a[i][j]+" ");

 			}

 			System.out.println();

 		}

	}

}

24、老式手机健盘上有1, 2, ..., 8, 9, 0键，其中每个键都代表多个字母，且0代表空格。输入一行只含字母和空格的字符串，将字符串转为成手机键盘按键序号，并输出结果

查看代码 
import java.util.Scanner;

public class java_10024 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String sentence = sc.nextLine();

		char[] a = sentence.toCharArray();

		for(int i = 0;i < a.length;i++)

		{

			if(a[i] >= 97 && a[i] <= 99)

				a[i] = '2';

			else if(a[i] >= 100 && a[i] <= 102)

				a[i] = '3';

			else if(a[i] >= 103 && a[i] <= 105)

				a[i] = '4';

			else if(a[i] >= 106 && a[i] <= 108)

				a[i] = '5';

			else if(a[i] >= 109 && a[i] <= 111)

				a[i] = '6';

			else if(a[i] >= 112 && a[i] <= 115)

				a[i] = '7';

			else if(a[i] >= 116 && a[i] <= 118)

				a[i] = '8';

			else if(a[i] >= 119 && a[i] <= 122)

				a[i] = '9';

			else if(a[i] == 32)

				a[i] = '0';

			System.out.print(a[i]);

		}

	}

}

25、输入一个正整数N，然后输入一个[2, 16]之间的数K，请把N转化为K进制的数，并输出结果

查看代码 
import java.util.Scanner;

public class java_10025 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int K = sc.nextInt();

		if(K < 2 || K > 16)

			return;

		//实现任意进制之间的相互转换

		String s = Integer.toString(N,K);

		System.out.println(s.toUpperCase());

	}

}

26、用散列表(哈希表)建立城市名主健与电话号码区号的映射，

查看代码 
import java.util.HashMap;

import java.util.Scanner;

public class java_10026 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		HashMap<String,String> code = new HashMap<String,String>();

		Scanner sc = new Scanner(System.in);

		int N = Integer.parseInt(sc.nextLine());

		//将城市名主键和电话号码区号建立映射存储在哈希表中

		for(int i = 0;i < N;i++)

		{

			String tempStr = sc.nextLine();

			String tempStrArr[] = tempStr.split(" ");

			code.put(tempStrArr[0], tempStrArr[1]);

		}

		int IN = Integer.parseInt(sc.nextLine());

		String[] cityKey = new String[IN];

		for(int i = 0;i < IN;i++)

		{

			String tempStr = sc.nextLine();

			cityKey[i] = tempStr;

		}

		sc.close();

		for(int i = 0;i < IN;i++)

		{

			System.out.println(cityKey[i] + " " + code.get(cityKey[i]));

		}

	}

}

27、请你定义一个类Student，表示学生，并实现相应的功能

查看代码 
import java.util.*;

import java.io.*;

public class java_10027 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		class Student{

			String Name;//姓名

			Double NGrade;//平时成绩

			Double EGrade;//考试成绩

			public Student(String Name,Double NGrade,Double EGrade){

				super();

				this.Name = Name;

				this.NGrade = NGrade;

				this.EGrade = EGrade;

			}

			public Student() {

				// TODO Auto-generated constructor stub

			}

			public String getName() {

				return this.Name;

			}

			public void setName(String Name) {

				this.Name = Name;

			}

			public Double getNGrade() {

				return NGrade;

			}

			public void setNGrade(Double NGrade) {

				this.NGrade = NGrade;

			}

			public double sumGrade(Student s) {

				return this.NGrade * 0.3 + this.EGrade * 0.7;

			}

			public boolean CompareTS(Student s) {

				 Double in = this.sumGrade();

			        Double out = s.sumGrade();

			        if (in > out)

			            return true;

			        else if (in == out)

			            return true;

			        else

			            return false;

			}

			private Double sumGrade() {

				// TODO Auto-generated method stub

				return null;

			}

			public void ToString(Student s) {

				System.out.printf("姓名:"+s.Name+"\n平时成绩:"+s.NGrade+"\n考试成绩:"+s.EGrade+"\n总成绩:"+sumGrade(s)+"\n");

			}

		}

	}

}

28、哎呀，题目又没写。。。

查看代码 
import java.io.*;

import java.util.*;

class Complex{

	double real;

	double image;

	public Complex(double real,double image) {

		this.real = real;

		this.image = image;

	}

	public Complex(Complex c) {

		this.real = c.real;

		this.image = c.image;

	}

	public double getReal() {

		return real;

	}

	public double getImage() {

		return image;

	}

	public void setReal(double real) {

		this.real = real;

	}

	public void setImage(double image) {

		this.image = image;

	}

	public String toString() {

		return "(" + String.format("%.5f", real) + ")" + "+" + "(" + String.format("%.5f", image) + ")" + "i";

	}

	public Complex add(Complex c) {

		return new Complex( this.real + c.real, this.image + c.image );

	}

	public Complex sub(Complex c) {

		return new Complex( this.real - c.real, this.image - c.image );

	}

	public Complex multiply( Complex C ) {

		double newa = this.real * C.real - this.image * C.image; // 新建一个 实部

		double newb = this.real * C.image + this.image * C.real; // 新建一个 虚部

		return new Complex( newa, newb );

	}

	public Complex exp( ) {

		return new Complex( Math.exp(this.real) * Math.cos(this.image),

		Math.exp(this.real) * Math.sin(this.image) );

	}

	public double abs( ) {

		return Math.sqrt( this.real * this.real + this.image * this.image );

	}

}

29、Rectangle实体类

查看代码 
import java.io.*;

import java.util.*;

class Rect {

	Double x;//X坐标

	Double y;//Y坐标

	Double L;//矩形长

	Double W;//矩形宽度

	public Rect(Double x,Double y,Double l,Double w) {

		this.x = x;

		this.y = y;

		this.L = l;

		this.W = w;

	}

	public Rect(Rect r) {

		// TODO Auto-generated constructor stub

		this.x = r.x;

		this.y = r.y;

		this.L = r.L;

		this.W = r.W;

	}

	public Double getX() {

		return this.x;

	}

	public void setX(Double x) {

		this.x = x;

	}

	public Double getY() {

		return this.y;

	}

	public void setY(Double y) {

		this.y = y;

	}

	public Double getL() {

		return this.L;

	}

	public void setL(Double l) {

		this.L = l;

	}

	public Double getW() {

		return this.W;

	}

	public void setW(Double w) {

		this.W = w;

	}

	public Double Area() {

		return L * W;

	}

	public int CompareArea(Rect r) {

		Double a = this.Area();

		Double b = r.Area();

		if(a > b)

			return 1;

		else if(a == b)

			return 0;

		else

			return -1;

	}

	public String  toString() {

		return (String.format("x:%.5f",x) +"\n" + String.format("y:%.5f", y) + "\n" + String.format("L:%.5f", L)+ "\n" + String.format("W:%.5f", W) +"\n" + String.format("面积:%.5f", this.Area()));

	}

}

30、请你定义一个类Circle，表示圆。要求实现相应的功能

查看代码 
public class java_10030 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		/* 构造函数参数按顺序为:x, y, r */

		Circle rc1 = new Circle(10.01, 20.0, 30.0);

		Circle rc2 = new Circle(rc1);

		System.out.println(String.valueOf(rc1.getX()));

		System.out.println(String.valueOf(rc1.getY()));

		System.out.println(String.valueOf(rc1.getR()));

		rc2.setX(40.66);

		rc2.setY(58.18);

		rc2.setR(28.98);

		/* 比较面积，如果rc2面积更大则输出1, 相等输出0，否则输出-1; */

		System.out.println(String.valueOf(rc2.CompareCS(rc1)));

		/* 比较周长，如果rc2周长更长则输出1, 相等输出0，否则输出-1; */

		System.out.println(String.valueOf(rc2.CompareCL(rc1)));

		System.out.println(String.valueOf(rc2.toString()));

	}

}

31、。。。

import java.io.*;

import java.util.*;

class CUser {

	String userName;

	String passWord;

	public CUser(String u,String p) {

		this.userName = u;

		this.passWord = p;

	}

	public String getUserName() {

		return this.userName;

	}

	public void setUserName(String u) {

		this.userName = u;

	}

	public String getPassWord() {

		return this.passWord;

	}

	public void setPassWord(String p) {

		this.passWord = p;

	}

	public String Login(String InUserName,String InPassWord) {

		if(userName.equals(InUserName) && passWord.equals(InPassWord))

			return "登录成功";

		else

			return "登陆失败";

	}

}

32、。。。

查看代码 
import java.io.*;

import java.util.*;

interface IReadBook {

	void ReadBook();

}

class CBauStu implements IReadBook{

	public void ReadBook() {

		System.out.println("本科生读教材");

	}

}

class CGduStu implements IReadBook{

	public void ReadBook() {

		System.out.println("硕士生读中文学术期刊");

	}

}

class CDocStu implements IReadBook{

	public void ReadBook() {

		System.out.println("博士生读外文学术期刊");

	}

}

33、直接看代码吧

查看代码 
import java.io.*;

import java.util.*;

interface ICry{

	void Cry();

}

class CFrog implements ICry{

	public void Cry() {

		System.out.println("青蛙哇哇叫");

	}

}

class CDog implements ICry{

	public void Cry() {

		System.out.println("小狗汪汪叫");

	}

}

class CCat implements ICry{

	public void Cry() {

		System.out.println("小猫喵喵叫");

	}

}

34、

查看代码 
public class java_10034 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Integer[] li = new Integer[] {100, 20, 32, 196, 85};

		 Integer iv = CommonFun.getMax(li);   //返回iv值为196

		 System.out.println(iv);

		 Double[] ld = new Double[] {51.0, 10.6, 165.2, 12.0, 82.0};

		 Double dv = CommonFun.getMax(ld);   //返回dv值为165.2

		 System.out.println(dv);

	}

}

35、

import java.util.Scanner;

public class java_10035 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		String[][] Student = new String[N][6];

		for(int i = 0;i < N;i++)

		{

			int sum =0;

			for(int j = 0;j < 4;j++)

			{

				Student[i][j] = sc.next();

			}

			sum = Integer.parseInt(Student[i][1]) + Integer.parseInt(Student[i][2]) + Integer.parseInt(Student[i][3]);

			Student[i][4] = "" + sum;

			Student[i][5] = "" + i;

		}

		//排序

		for(int i = 0;i < N -1;i++)

		{

			for(int j = N -1;j > i;j--)

			{

				if(Integer.parseInt(Student[i][4]) < Integer.parseInt(Student[j][4]))

				{

					String[] tempArr = Student[i];

					Student[i] = Student[j];

					Student[j] = tempArr;

				}else if(Integer.parseInt(Student[i][4]) == Integer.parseInt(Student[j][4]))

				{

					if(Integer.parseInt(Student[i][5]) > Integer.parseInt(Student[j][5]))

					{

						String[] tempArr = Student[i];

						Student[i] = Student[j];

						Student[j] = tempArr;

					}

				}

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < 5;j++)

			{

				System.out.print(Student[i][j] + " ");

			}

			System.out.println();

		}

	}

}

36、

import java.util.Scanner;

public class java_10036 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		String[][] Student = new String[N][6];

		for(int i = 0;i < N;i++)

		{

			int sum =0;

			for(int j = 0;j < 4;j++)

			{

				Student[i][j] = sc.next();

			}

			sum = Integer.parseInt(Student[i][1]) + Integer.parseInt(Student[i][2]) + Integer.parseInt(Student[i][3]);

			Student[i][4] = "" + sum;

			Student[i][5] = "" + i;

		}

		//排序

		for(int i = 0;i < N -1;i++)

		{

			for(int j = N -1;j > i;j--)

			{

				if(Integer.parseInt(Student[i][4]) < Integer.parseInt(Student[j][4]))

				{

					String[] tempArr = Student[i];

					Student[i] = Student[j];

					Student[j] = tempArr;

				}else if(Integer.parseInt(Student[i][4]) == Integer.parseInt(Student[j][4]))

				{

					if(Integer.parseInt(Student[i][1]) < Integer.parseInt(Student[j][1]))

					{

						String[] tempArr = Student[i];

						Student[i] = Student[j];

						Student[j] = tempArr;

					}else if(Integer.parseInt(Student[i][1]) == Integer.parseInt(Student[j][1])) {

						if(Integer.parseInt(Student[i][5]) > Integer.parseInt(Student[j][5]))

						{

							String[] tempArr = Student[i];

							Student[i] = Student[j];

							Student[j] = tempArr;

						}

					}

				}

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < 5;j++)

			{

				System.out.print(Student[i][j] + " ");

			}

			System.out.println();

		}

	}

}

37、

import java.util.Scanner;

public class java_10037 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		String[][] Student = new String[N][6];

		for(int i = 0;i < N;i++)

		{

			int sum =0;

			for(int j = 0;j < 4;j++)

			{

				Student[i][j] = sc.next();

			}

			sum = Integer.parseInt(Student[i][1]) + Integer.parseInt(Student[i][2]) + Integer.parseInt(Student[i][3]);

			Student[i][4] = "" + sum;

			Student[i][5] = "" + i;

		}

		//排序

		for(int i = 0;i < N -1;i++)

		{

			for(int j = N -1;j > i;j--)

			{

				if(Integer.parseInt(Student[i][4]) < Integer.parseInt(Student[j][4]))

				{

					String[] tempArr = Student[i];

					Student[i] = Student[j];

					Student[j] = tempArr;

				}else if(Integer.parseInt(Student[i][4]) == Integer.parseInt(Student[j][4]))

				{

					if(Integer.parseInt(Student[i][1]) < Integer.parseInt(Student[j][1]))

					{

						String[] tempArr = Student[i];

						Student[i] = Student[j];

						Student[j] = tempArr;

					}else if(Integer.parseInt(Student[i][1]) == Integer.parseInt(Student[j][1])) {

						if(Integer.parseInt(Student[i][2]) < Integer.parseInt(Student[j][2]))

						{

							String[] tempArr = Student[i];

							Student[i] = Student[j];

							Student[j] = tempArr;

						}else if(Integer.parseInt(Student[i][2]) == Integer.parseInt(Student[j][2]))

							if(Integer.parseInt(Student[i][5]) > Integer.parseInt(Student[j][5]))

							{

								String[] tempArr = Student[i];

								Student[i] = Student[j];

								Student[j] = tempArr;

							}

					}

				}

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < 5;j++)

			{

				System.out.print(Student[i][j] + " ");

			}

			System.out.println();

		}

	}

}

38、

import java.util.Scanner;

public class java_10038 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		String[][] Student = new String[N][6];

		for(int i = 0;i < N;i++)

		{

			int sum =0;

			for(int j = 0;j < 4;j++)

			{

				Student[i][j] = sc.next();

			}

			sum = Integer.parseInt(Student[i][1]) + Integer.parseInt(Student[i][2]) + Integer.parseInt(Student[i][3]);

			Student[i][4] = "" + sum;

			Student[i][5] = "" + i;

		}

		//排序

		for(int i = 0;i < N -1;i++)

		{

			for(int j = N -1;j > i;j--)

			{

				if(Integer.parseInt(Student[i][4]) < Integer.parseInt(Student[j][4]))

				{

					String[] tempArr = Student[i];

					Student[i] = Student[j];

					Student[j] = tempArr;

				}else if(Integer.parseInt(Student[i][4]) == Integer.parseInt(Student[j][4]))

				{

					if(Integer.parseInt(Student[i][1]) < Integer.parseInt(Student[j][1]))

					{

						String[] tempArr = Student[i];

						Student[i] = Student[j];

						Student[j] = tempArr;

					}else if(Integer.parseInt(Student[i][1]) == Integer.parseInt(Student[j][1])) {

						if(Integer.parseInt(Student[i][2]) < Integer.parseInt(Student[j][2]))

						{

							String[] tempArr = Student[i];

							Student[i] = Student[j];

							Student[j] = tempArr;

						}else if(Integer.parseInt(Student[i][2]) == Integer.parseInt(Student[j][2]))

							if(Student[i][0].compareTo(Student[j][0]) > 0)

							{

								String[] tempArr = Student[i];

								Student[i] = Student[j];

								Student[j] = tempArr;

							}

					}

				}

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < 5;j++)

			{

				System.out.print(Student[i][j] + " ");

			}

			System.out.println();

		}

	}

}

39、

import java.io.*;

import java.util.Scanner;

public class java_10039 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str = sc.nextLine();

		int flag = -1 , i = 0;

		char[] ch = str.toCharArray();

		while(i < str.length()/2)

		{

			if(ch[i] != ch[str.length() -1 -i])

			{

				flag = 0;

				break;

			}

			i++;

		}

		if(flag ==-1)

		{

			flag = 1;

		}

		System.out.println(flag);

	}

}

40、

import java.util.Scanner;

public class java_10040 {

	public String longStr(String s)

	{

		if(s.length() < 2)

			return s;

		int max_len = 1;

		int start = 0;

		//dp[i][j]表示s[i][j]是否是回文串

		boolean[][] dp = new boolean[s.length()][s.length()];

		//初始化，所有长度为1的字串都是回文串

		for(int i = 0;i < s.length();i++)

		{

			dp[i][i] = true;

		}

		char[] charArr = s.toCharArray();

		//递推开始

		//先枚举字串长度

		for(int l = 2;l <= s.length();l++)

		{

			//枚举左边界

			for(int i = 0;i < s.length();i++)

			{

				int j = l + i - 1;

				//如果右边越界，则退出循环

				if(j >= s.length())

					break;

				if(charArr[i] != charArr[j]) {

					dp[i][j] = false;

				}

				else {

					if(j - i < 3) {

						dp[i][j] = true;

					}

					else {

						dp[i][j] = dp[i + 1][j - 1];

					}

				}

				//只要dp[j][k] == true成立，就表示子串s[i][j]是回文

				if(dp[i][j] && j - i + 1 > max_len) {

					max_len = j - i + 1;

					start = i;

				}

			}

		}

		return s.substring(start,start + max_len);

	}

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		String str = sc.nextLine();

		java_10040 solution = new java_10040();

		System.out.println(solution.longStr(str));

	}

}

41、输入正整数N和K，然后输入N个浮点数，要求输出它们中第K大的数

查看代码 
import java.util.Scanner;

public class java_10041 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int K = sc.nextInt();

		Double Temp;

		Double[] Arr = new Double[N];

		for(int i = 0; i < Arr.length;i++)

		{

			Arr[i] = sc.nextDouble();

		}

		//利用冒泡排序法对数组进行排序

		for(int i = 0;i < Arr.length - 1 ;i++)

		{

			for(int j = 0;j <Arr.length - i - 1;j++)

			{

				if(Arr[j] < Arr[j + 1])

				{

					Temp = Arr[j];

					Arr[j] = Arr[j + 1];

					Arr[j + 1] = Temp;

				}

			}

		}

		System.out.printf("%.5f",Arr[K-1]);

	}

}

42、输入正整数N，然后输入N个浮点数组成的向量A，再输入N个浮点数组成的向量B，要求计算并输出A+B。

查看代码 
import java.util.Scanner;

public class java_10042 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		Double[] A = new Double[N];

		Double[] B = new Double[N];

		for(int i = 0; i < N;i++)

		{

			A[i] = sc.nextDouble();

		}

		for(int i = 0; i < N;i++)

		{

			B[i] = A[i] + sc.nextDouble();

		}

		for(int i = 0;i < N;i++)

		{

			System.out.print(String.format("%.5f" + " ", B[i]));

		}

	}

}

43、输入正整数N，然后输入N个浮点数组成的向量A，再输入N个浮点数组成的向量B，要求计算并输出A-B。

查看代码 
import java.util.Scanner;

public class java_10043 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		Double[] A = new Double[N];

		Double[] B = new Double[N];

		for(int i = 0; i < N;i++)

		{

			A[i] = sc.nextDouble();

		}

		for(int i = 0; i < N;i++)

		{

			B[i] = A[i] - sc.nextDouble();

		}

		for(int i = 0;i < N;i++)

		{

			System.out.print(String.format("%.5f" + " ", B[i]));

		}

	}

}

44、输入正整数N，然后输入N个浮点数组成的向量A，再输入N个浮点数组成的向量B，要求计算并输出向量A和B之间的欧氏距离

查看代码 
import java.util.Scanner;

public class java_10044 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		Double[] A = new Double[N];

		Double[] B = new Double[N];

		Double sum = 0.0;

		for(int i = 0;i < N;i++)

		{

			A[i] = sc.nextDouble();

		}

		for(int i = 0;i < N;i++)

		{

			 B[i]= sc.nextDouble();

			sum += Math.pow(A[i] - B[i] , 2);

		}

		sum = Math.sqrt(sum);

		System.out.println(String.format("%.5f",sum));

	}

}

45、输入正整数N和K，然后输入一个由N个浮点数组成的向量A，再输入K个同样维度的向量，要求在K个向量中找出与向量A的欧氏距离最小的向量，并输出找到的向量与向量A的欧氏距离

查看代码 
import java.util.Scanner;

public class java_10045 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int K = sc.nextInt();

		Double[] A = new Double[N];

		for(int i = 0;i < A.length;i++)

		{

			A[i] = sc.nextDouble();

		}

		Double[][] B = new Double[K][N];

		for(int i = 0;i < B.length;i++)

		{

			for(int j = 0;j < B[i].length;j++)

			{

				B[i][j] = sc.nextDouble();

			}

		}

		//求欧氏距离

		Double[] V = new Double[K];

		for(int i = 0;i < K;i++)

		{

			double value = 0;

			for(int j = 0;j < N;j++)

			{

				value += Math.pow(A[j] - B[i][j],2);

			}

			V[i] = Math.sqrt(value);

		}

		//寻找与向量A的欧氏距离最小的向量

		double minValue = V[0];

		for(int i = 1 ;i < V.length;i++)

		{

			if(V[i] < minValue)

				minValue = V[i];

		}

		System.out.printf("%.5f",minValue);

	}

}

46、输入正整数N和K，然后输入K个向量，其中每个向量由N个浮点数组成。现要求在K个向量中找出欧氏距离最小的两个向量，并输出找到的这两个向量之间的欧氏距离

查看代码 
import java.util.Scanner;

public class java_10046 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int K = sc.nextInt();

		double sum = 0.0;

		double minSum = Double.MAX_VALUE;

		int minI = -1;

		int minJ = -1;

		Double[][] data= new Double[K][N];

		for(int i = 0;i < K;i++)

		{

			for(int j = 0 ;j < N;j++)

			{

				data[i][j] = sc.nextDouble();

			}

		}

		for(int i = 0 ;i < K;i++)

		{

			for(int j = i + 1;j < K;j++)

			{

				sum = 0.0;

				for(int m = 0;m < N;m++)

				{

					sum = sum + Math.pow(data[i][m] - data[j][m],2);

				}

				sum = Math.sqrt(sum);

				if(sum < minSum)

				{

					minSum = sum;

					minI =i;

					minJ = j;

				}

			}

		}

		System.out.format("%.5f",minSum);

	}

}

47、。。。

48、。。。

import java.util.Scanner;

public class java_10048 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		Double[] M = new Double[N];

		Double[] A = new Double[N];

		Double[] B = new Double[N];

		Double[] R = new Double[N];

		for(int i = 0;i < N;i++)

		{

			M[i] = sc.nextDouble();

		}

		for(int i = 0;i < N;i++)

		{

			A[i] = sc.nextDouble();

		}

		for(int i = 0;i < N;i++)

		{

			B[i] = sc.nextDouble();

		}

		for(int i = 0;i < N;i++)

		{

			if(M[i] < 0.5)

			{

				R[i] = A[i];

			}

			else

			{

				R[i] = B[i];

			}

		}

		for(int i = 0;i < N;i++)

		{

			System.out.format("%.5f" + " ", R[i]);

		}

	}

}

49、。。。

import java.util.Scanner;

	public class java_10049 {

		public static void main(String[] args) {

			// TODO Auto-generated method stub

			Scanner sc = new Scanner(System.in);

			int N1 = sc.nextInt();

			int C1 = sc.nextInt();

			int N2 = sc.nextInt();

			int C2 = sc.nextInt();

			Double[][] A = new Double[N1][C1];

			Double[][] B = new Double[N2][C2];

			for(int i = 0;i < N1;i++)

			{

				for(int j = 0;j < C1;j++)

				{

					A[i][j] = sc.nextDouble();

				}

			}

			for(int i = 0;i < N2;i++)

			{

				for(int j = 0;j < C2;j++)

				{

					B[i][j] = sc.nextDouble();

				}

			}

			for(int i = 0;i < N1;i++)

			{

				for(int j = 0;j < C2;j++)

				{

					Double sum = 0.0;

					for(int k = 0;k < C1;k++)

					{

						sum = sum + A[i][k]*B[k][j];

					}

					System.out.format("%.5f" + " ", sum);

				}

				System.out.println();

			}

		}

	}

50、51、没写啊哈哈哈哈哈哈

52、。。。

import java.util.Scanner;

public class java_10052 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int C = sc.nextInt();

		Double[][] M = new Double[N][C];

		Double[][] A = new Double[N][C];

		Double[][] B = new Double[N][C];

		Double[][] R = new Double[N][C];

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < C;j++)

			{

				M[i][j] = sc.nextDouble();

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < C;j++)

			{

				A[i][j] = sc.nextDouble();

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < C;j++)

			{

				B[i][j] = sc.nextDouble();

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < C;j++)

			{

				if(M[i][j] < 0.5)

				{

					R[i][j] = A[i][j];

				}

				else

				{

					R[i][j] = B[i][j];

				}

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < C;j++)

			{

				System.out.format("%.5f" + " ", R[i][j]);

			}

			System.out.println();

		}

	}

}

53、。。

import java.util.Scanner;

public class java_10053 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int[][] data = new int[N][N];

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < N;j++)

			{

				data[i][j] = sc.nextInt();

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = N - 1;j > -1;j--)

			{

				System.out.print(data[i][j] + " ");

			}

			System.out.println();

		}

	}

}

54、。。。

import java.util.Scanner;

public class java_10054 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int[][] data = new int[N][N];

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < N;j++)

			{

				data[i][j] = sc.nextInt();

			}

		}

		for(int i = N - 1;i > -1;i--)

		{

			for(int j = N - 1;j > -1;j--)

			{

				System.out.print(data[j][i] + " ");

			}

			System.out.println();

		}

	}

}

55、。。。

import java.util.Scanner;

public class java_10055 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int[][] data = new int[N][N];

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < N;j++)

			{

				data[i][j] = sc.nextInt();

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = N - 1;j > -1;j--)

			{

				System.out.print(data[j][i] + " ");

			}

			System.out.println();

		}

	}

}

56、

import java.util.Scanner;

public class java_10055 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int N = sc.nextInt();

		int[][] data = new int[N][N];

		for(int i = 0;i < N;i++)

		{

			for(int j = 0;j < N;j++)

			{

				data[i][j] = sc.nextInt();

			}

		}

		for(int i = 0;i < N;i++)

		{

			for(int j = N - 1;j > -1;j--)

			{

				System.out.print(data[j][i] + " ");

			}

			System.out.println();

		}

	}

}

57、忘写了 OvO

58、

import java.util.Scanner;

public class java_10058 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		Scanner sc = new Scanner(System.in);

		int count = 0;

		String str = sc.nextLine();

		for(int i = 0;i < str.length();i++)

		{

			if(count < 0)

				break;

			String temp = str.substring(i,i + 1);

			if(temp.equals("("))

				count ++;

			if(temp.equals(")"))

				count --;

		}

		if(count == 0)

			System.out.println(1);

		else

			System.out.println(0);

	}

}

59、

import java.util.Scanner;

import java.math.BigDecimal;

import java.util.ArrayList;

import java.util.List;

import java.util.Stack;

public class java_10059 {

	public static void main(String[] args) {

		// TODO Auto-generated method stub

		@SuppressWarnings("resource")

		Scanner sc=new Scanner(System.in);

		String str=sc.nextLine();

		BigDecimal result=cal(str);

		System.out.format("%.5f\n",result);

	}

	public static BigDecimal cal(String str)

	{

		List<String> list=new ArrayList<>();

		char[] arr=str.toCharArray();

		StringBuffer sb=new StringBuffer();

		for(char c:arr)

		{

			if(c>='0'&&c<='9') {

				sb.append(c);

			}else if(c=='.')

			{

				if(sb.indexOf(".")>0)

				{

					throw new RuntimeException("非法字符");

				}

				sb.append(c);

			}

			else if(c=='+'||c=='-'||c=='*'||c=='/'||c=='('||c==')') {

				if(sb.length()>0)

				{

					list.add(sb.toString());

					sb.setLength(0);

				}

				list.add(c+"");

			}

			else if(c==' ')

			{

				continue;

			}else {

				throw new RuntimeException("非法字符");

			}

		}

		if(sb.length()>0)

		{

			list.add(sb.toString());

		}

		List<String> strList =new ArrayList<>();

		Stack<String> stack=new Stack<>();

		String temp;

		for(String s:list)

		{

			if(s.equals("("))

			{

				stack.push(s);

			}

			else if(s.equals(")")) {

				while(!(temp=stack.pop()).equals("("))

				{

					strList.add(temp);

				}

			}

			else if (s.equals("*")||s.equals("/")) {

				while(!stack.isEmpty()) {

					temp=stack.peek();

					if(temp.equals("*")||temp.equals("/"))

					{

						stack.pop();

						strList.add(temp);

					}else {

						break;

					}

				}

				stack.push(s);

			}else if(s.equals("+")||s.equals("-"))

			{

				while(!stack.isEmpty()) {

					temp=stack.peek();

					if(!temp.equals("("))

					{

						stack.pop();

						strList.add(temp);

					}else {

						break;

					}

				}

				stack.push(s);

			}

			else {

				strList.add(s);

			}

		}

		while(!stack.isEmpty()) {

			strList.add(stack.pop());

		}

		Stack<BigDecimal>newStack=new Stack<>();

		for(String s:strList)

		{

			if(s.equals("+")||s.equals("-")||s.equals("*")||s.equals("/")) {

				BigDecimal b1=newStack.pop();

				BigDecimal b2=newStack.pop();

				switch(s){

					case "+":

					    newStack.push(b2.add(b1));

					    break;

					case "-":

						newStack.push(b2.subtract(b1));

						break;

					case "*":

						newStack.push(b2.multiply(b1));

						break;

					case "/":

						newStack.push(b2.divide(b1,9,BigDecimal.ROUND_HALF_UP));

						break;

				}

			}

			else {

				newStack.push(new BigDecimal(s));

			}

		}

		return newStack.peek();

	}

}

60、

import java.util.Scanner;

import java.math.BigDecimal;

import java.util.ArrayList;

import java.util.List;

import java.util.Stack;

public class java_10060{

    public static void main(String[] args) throws Exception{

    	@SuppressWarnings("resource")

		Scanner sc=new Scanner(System.in);

		String str=sc.nextLine().replace(" ", "");

		BigDecimal result=cal(str);

		System.out.format("%.5f\n",result);

	}

	public static BigDecimal cal(String str)

	{

		List<String> list=new ArrayList<>();

		char[] arr=str.toCharArray();

		StringBuffer sb=new StringBuffer();

		for(char c:arr)

		{

			if(c>='0'&&c<='9') {

				sb.append(c);

			}else if(c=='.')

			{

				if(sb.indexOf(".")>0)

				{

					throw new RuntimeException("非法字符");

				}

				sb.append(c);

			}

			else if(c=='+'||c=='-'||c=='*'||c=='/'||c=='('||c==')') {

				if(sb.length()>0)

				{

					list.add(sb.toString());

					sb.setLength(0);

				}

				list.add(c+"");

			}

			else if(c==' ')

			{

				continue;

			}else {

				throw new RuntimeException("非法字符");

			}

		}

		if(sb.length()>0)

		{

			list.add(sb.toString());

		}

		List<String> strList =new ArrayList<>();

		Stack<String> stack=new Stack<>();

		String temp;

		for(String s:list)

		{

			if(s.equals("("))

			{

				stack.push(s);

			}

			else if(s.equals(")")) {

				while(!(temp=stack.pop()).equals("("))

				{

					strList.add(temp);

				}

			}

			else if (s.equals("*")||s.equals("/")) {

				while(!stack.isEmpty()) {

					temp=stack.peek();

					if(temp.equals("*")||temp.equals("/"))

					{

						stack.pop();

						strList.add(temp);

					}else {

						break;

					}

				}

				stack.push(s);

			}else if(s.equals("+")||s.equals("-"))

			{

				while(!stack.isEmpty()) {

					temp=stack.peek();

					if(!temp.equals("("))

					{

						stack.pop();

						strList.add(temp);

					}else {

						break;

					}

				}

				stack.push(s);

			}

			else {

				strList.add(s);

			}

		}

		while(!stack.isEmpty()) {

			strList.add(stack.pop());

		}

		Stack<BigDecimal>newStack=new Stack<>();

		for(String s:strList)

		{

			if(s.equals("+")||s.equals("-")||s.equals("*")||s.equals("/")) {

				BigDecimal b1=newStack.pop();

				BigDecimal b2=newStack.pop();

				switch(s){

					case "+":

					    newStack.push(b2.add(b1));

					    break;

					case "-":

						newStack.push(b2.subtract(b1));

						break;

					case "*":

						newStack.push(b2.multiply(b1));

						break;

					case "/":

						newStack.push(b2.divide(b1,9,BigDecimal.ROUND_HALF_UP));

						break;

				}

			}

			else {

				newStack.push(new BigDecimal(s));

			}

		}

		return newStack.peek();

    }

}

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