UVA - 524 Prime Ring Problem Time Limit:3000MS     Memory Limit:0KB     64bit IO Format:%lld & %llu Description A ring is composed of n (even number) circles as shown in diagram. Put natural numbers  into each circle separately, and the sum of number…

题意  把1到n这n个数以1为首位围成一圈  输出全部满足随意相邻两数之和均为素数的全部排列 直接枚举排列看是否符合肯定会超时的  n最大为16  利用回溯法 边生成边推断  就要快非常多了 #include<cstdio> using namespace std; const int N = 50; int p[N], vis[N], a[N], n; int isPrime(int k) { for(int i = 2; i * i <= k; ++i) if(k % i == 0)…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 34846    Accepted Submission(s): 15441 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

  Prime Ring Problem  A ring is composed of n (even number) circles as shown in diagram. Put natural numbers into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle should always…

题意:输入n,把1~n组成个环,相邻两个数之和为素数. 分析:回溯法. #pragma comment(linker, "/STACK:102400000, 102400000") #include<cstdio> #include<cstring> #include<cstdlib> #include<cctype> #include<cmath> #include<iostream> #include<s…

传送门 Description A ring is composed of n (even number) circles as shown in diagram. Put natural numbers 1, 2, . . . , n into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle sho…

题意:给出n,把从1到n排成一个环,输出相邻两个数的和为素数的序列 照着紫书敲的, 大概就是这个地方需要注意下,初始化的时候a[0]=1,然后dfs(1),从第1个位置开始搜 #include<iostream> #include<cstdio> #include<cstring> #include <cmath> #include<stack> #include<vector> #include<map> #includ…

题目大意:输入正整数n,把整数1,2...,n组成一个环,使得相邻两个整数之和均为素数.输出时从整数1开始逆时针(题目中说的不是很明白??)排列.同一个环应恰好输出一次. 枚举,并在枚举每一个数是进行判断,可以提高效率. #include <cstdio> #include <cstring> ], vis[]; int n; int is_prime(int n) { ; i*i <= n; i++) ) ; ; } void dfs(int cur) { ]+A[n-])…

dfs练习题,我素数打表的时候j=i了,一直没发现实际上是j=i*i,以后可记住了.还有最后一行不能有空格...昏迷了半天 我的代码(紫书上的算法) #include <bits/stdc++.h> using namespace std; int bk[110]; int num[110]; int vis[110]; int n; void db() { for(int i=2;i*i<=100;i++) if(!bk[i]) for(int j=i*i;j<=100;j+=i…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1016 Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Problem Description A ring is compose of n circles as shown in diagram. Put natural number 1, 2…

如果用全排列生成之后,在判断是否是素数环是会超时的,应该用回溯. 回溯的时候  首先要注意 递归边界 ,结束的时候别忘记判断最后一个和第一个元素能否成立  还有要记得vis的使用和递归之后的清理. #include <cstdio> #include <cstring> using namespace std; ; +],vis [+]; +]; void dfs(int cur) { ]+a[]]) { printf(]); ;i<n;i++) printf("…

题目链接:Uva 552 思路分析:时间限制为3s,数据较小,使用深度搜索查找所有的解. 代码如下: #include <iostream> #include <string.h> using namespace std; ; int n; int A[MAX_N], vis[MAX_N]; int is_prime( int n ) { ) return true; ; i * i <= n; ++i ) ) return false; return true; } voi…

本文链接:http://www.cnblogs.com/Ash-ly/p/5398684.html 题意: 给你一个数字N(N <= 20),要求你把这N个数组成一个环,环内的数字不能重复,左右相邻的两个的和是素数.给出最后的答案. 思路: 利用回溯剪枝算法,N个数,每个数有N种状态,枚举这N个状态,枚举过程中剪枝优化. 代码: #include <cstdio> #include <iostream> #include <cstring> #include &l…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 42600    Accepted Submission(s): 18885 Problem Description A ring is compose of n circles as shown in diagram. Put natural num…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 34609    Accepted Submission(s): 15327 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

题目OJ地址: https://www.luogu.org/problemnew/show/UVA524 hdu oj 1016:  https://vjudge.net/problem/HDU-1016 zoj 1457  :https://vjudge.net/problem/ZOJ-1457 题意翻译 输入正整数n,把整数1,2,...,n组成一个环,使得相邻两个整数之和均为素数.输出时,从整数1开始逆时针排列.同一个环恰好输出一次.. 多组数据,读入到EOF结束. 第i组数据输出前加上一…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 12105    Accepted Submission(s): 5497 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

  Prime Ring Problem                                                                       时间限制: 2000ms               内存限制: 32768KB                HDU       ID: 1016 题目描述 A ring is compose of n circles as shown in diagram. Put natural number 1, 2, ..…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 18313    Accepted Submission(s): 8197 Problem Description A ring is compose of n circles as shown in diagram. Put natural numbe…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 23458    Accepted Submission(s): 10465 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 31031    Accepted Submission(s): 13755 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

Prime Ring Problem Time Limit : 4000/2000ms (Java/Other)   Memory Limit : 65536/32768K (Java/Other) Total Submission(s) : 18   Accepted Submission(s) : 7 Problem Description A ring is compose of n circles as shown in diagram. Put natural number 1, 2,…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 20105    Accepted Submission(s): 9001 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

Problem Description A ring is compose of n circles as shown in diagram. Put natural number 1, 2, ..., n into each circle separately, and the sum of numbers in two adjacent circles should be a prime. Note: the number of first circle should always be 1…

题目连接:http://acm.hdu.edu.cn/showproblem.php?pid=1016 Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 34554    Accepted Submission(s): 15303 Problem Description A ring is compos…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 40339    Accepted Submission(s): 17813 Problem Description A ring is compose of n circles as shown in diagram. Put natural num…

 Prime Ring Problem Time Limit: 10 Seconds      Memory Limit: 32768 KB A ring is compose of n circles as shown in diagram. Put natural number 1, 2, ..., n into each circle separately, and the sum of numbers in two adjacent circles should be a prime…

题目链接:http://ac.jobdu.com/problem.php?pid=1459 详解链接:https://github.com/zpfbuaa/JobduInCPlusPlus 参考代码: // // 1459 Prime ring problem.cpp // Jobdu // // Created by PengFei_Zheng on 23/04/2017. // Copyright © 2017 PengFei_Zheng. All rights reserved. // #…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 21151    Accepted Submission(s): 9465 Problem Description A ring is compose of n circles as shown in diagram. Put natural numb…

Prime Ring Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 25156    Accepted Submission(s): 11234 Problem Description A ring is compose of n circles as shown in diagram. Put natural num…