Java 之进制转换

//十进制转十六进制

 import java.util.Scanner;
 public class Main{
 public static void main(String[] args){
 Scanner input = new Scanner(System.in);
 int n;
 n=input.nextInt();
 System.out.println(Integer.toHexString(n).toUpperCase());//转换成大写字母；toLowerCase()：转换成小写的16进制；
   }
 }

//各种进制转换

 import java.util.Scanner;
 public class Main {
     public static void main(String[] args) {
         Scanner sc=new Scanner(System.in);
        String c=sc.next();
        System.out.println(Integer.toHexString(c).toUpperCase());//十进制转换成十六进制
         System.out.println(Integer.toBinaryString(c).toUpperCase());//十进制转换成2进制
         System.out.println(Integer.toOctalString(c).toUpperCase());//十进制转换成八进制
        System.out.println(Integer.valueOf(c,).toString());//十六进制转换成十进制
        String t=Integer.valueOf(c, ).toString();
        int n=Integer.parseInt(t);//先将十六进制转换成字符串然后将字符串转换成整数
        System.out.println(Integer.toOctalString(n).toUpperCase());//整数转换成八进制
     }
 }

//十六进制转八进制（太长的java不行了）用c

 #include <stdio.h>
 #include<cstring>
 int x2i(char c)
 {
     if (c >= 'A')
         return c - ;
     else
         return c - ;
 }

 int main()
 {
     int i, j, n;
     char a[][];
     scanf("%d", &n);
     for (i = ; i < n; i++)
         scanf("%s", a[i]);
     for (i = ; i < n; i++)
     {
         char* p = a[i];
         int len = strlen(p);
         if (len %  == )
         {
             printf("%o", x2i(p[]));
             j = ;
         }
         else if (len %  == )
         {
             printf("%o", x2i(p[])*+x2i(p[]));
             j = ;
         }
         else
         {
             printf("%o", x2i(p[])*+x2i(p[])*+x2i(p[]));
             j = ;
         }
         for (; j < len; j += )
             printf("%04o", x2i(p[j])*+x2i(p[j+])*+x2i(p[j+]));
         printf("\n");
     }
     return ;
 }