Problem Description Given a set of sticks of various lengths, is it possible to join them end-to-end to form a square?   Input The first line of input contains N, the number of test cases. Each test case begins with an integer 4 <= M <= 20, the numb…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1518 题目大意:根据题目所给的几条边,来判断是否能构成正方形,一个很好的深搜应用,注意剪枝,以防超时! #include <iostream> #include <cstdio> #include<algorithm> #include <cstring> using namespace std; ],visit[]; int l,n; int dfs(int…

Square Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 9588    Accepted Submission(s): 3127 Problem Description Given a set of sticks of various lengths, is it possible to join them end-to-end…

题目链接 题目大意: 题意就是输入棍子的数量和每根棍子的长度,看能不能拼成正方形. #include <bits/stdc++.h> using namespace std; int n,m,sum,cur; ],vis[]; bool fp; bool mycmp(int a,int b){ return a>b; } void dfs(int s,int len,int num){ //当前位置,目前长度,成功条数 ){ fp=true;return; } ,,num+); //如果…

Problem Description Given a set of sticks of various lengths, is it possible to join them end-to-end to form a square? Input The first line of input contains N, the number of test cases. Each test case begins with an integer 4 <= M <= 20, the number…

解题思路:sum%4!=0    , max<sum/4 #include<iostream>#include<cstdio>#include<cstring>#include<string>#include<algorithm>usingnamespace std;int a[100];bool vis[100],flag;int m,ave;bool dfs(int ans,int sum,int cnt){     if(sum==a…

Square HDU 1518 搜索 题意 原题链接 给你一定若干个木棒,让你使用它们组成一个四边形,要求这些木棒必须全部使用. 解题思路 木棒有多种组合方式,使用搜索来进行寻找,这里需要进行优化,不然复杂度非常高. 因为M最大为20,所以,如果用DFS还是可以接受的. 由所有火柴棒的长度和,我们可以求出要组成正方形的边长.我们设边长为len.在搜索前,首先可以把边长为分数的,也就是火柴棒的长度和不能被4整除的,排除掉. 问题可以转化为从M个数中挑出4组和为len的数. 首先,从M个数中搜索出和…

HDOJ1518 Square Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 11375    Accepted Submission(s): 3660 Problem Description Given a set of sticks of various lengths, is it possible to join them e…

本题来自:http://acm.hdu.edu.cn/showproblem.php?pid=1518 题意:输入几个长度,判断能否拼成正方形. 以下部分参考了网友代码,终于ac啦. #include <stdio.h> #include <string.h> #include <stdlib.h> ]; ]; int len,m; int comp ( const void *a, const void *b ){return * ( int * ) a - * (…

hdu 5468 Puzzled Elena   /*快速通道*/ Sample Input 5 1 2 1 3 2 4 2 5 6 2 3 4 5   Sample Output Case #1: 1 1 0 0 0 题意:在一棵树上,每个节点有值,求以x为根节点的树中,有多少与根节点互质 思路: 用num[i]记录节点中包含因子i的个数,然后搜索到当前根节点时,我们先记录下在此之前的num,然后遍历返回后, 计算num的差值,利用莫比乌斯原理,先ans记录树中所有的节点数,然后该加的加,该减…