题目传送门 /* DFS:问能否用小棍子组成一个正方形 剪枝有3:长的不灵活,先考虑:若根本构不成正方形,直接no:若第一根比边长长,no 这题是POJ_1011的精简版:) */ #include <cstdio> #include <iostream> #include <cstring> #include <map> #include <set> #include <cmath> #include <algorithm&g…

传送门:http://poj.org/problem?id=2362 题目大意: 给一些不同长度的棍棒,问是否可能组成正方形. 学习了写得很好的dfs 赶紧去玩博饼了.....晚上三个地方有约.....T T分身乏术啊.... #include<cstdio> #include<algorithm> using namespace std; const int MAXN=22; int side[MAXN],target,n; bool vis[MAXN]; bool dfs(in…

题意:给n个木棍,问能不能正好拼成一个正方形. 解法:POJ1011的简单版……不需要太多剪枝……随便剪一剪就好了……但是各种写屎来着QAQ 代码: #include<stdio.h> #include<iostream> #include<algorithm> #include<string> #include<string.h> #include<math.h> #include<limits.h> #include&…

Square Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 21821   Accepted: 7624 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 nu…

题目大意:给你T组数据,每组数据有n个棍子,问你能不能用这些棍子拼成一个正方形(所有都要用上,而且不能截断棍子). Sample Input 34 1 1 1 15 10 20 30 40 508 1 7 2 6 4 4 3 5Sample Output yesnoyes 芒果君:我以为这只是一道简单的dfs,没想到它虽然是简单的dfs,结果为了剪枝到不tle,耗了我整整两节自习课,人家明明和题解写的差不多来着,嘤嘤嘤,人家超想哭的>_< 至于怎么剪枝代码里已经很明显了,不容易想到的是,如果已…

Square Ice Description Square Ice is a two-dimensional arrangement of water molecules H2O, with oxygen at the vertices of a square lattice and one hydrogen atom between each pair of adjacent oxygen atoms. The hydrogen atoms must stick out on the left…

Description The left figure below shows a complete 3*3 grid made with 2*(3*4) (=24) matchsticks. The lengths of all matchsticks are one. You can find many squares of different sizes in the grid. The size of a square is the length of its side. In the…

目录 题面 思路 思路 AC代码 题面 Square Ice Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 4526   Accepted: 1759 Description Square Ice is a two-dimensional arrangement of water molecules H2O, with oxygen at the vertices of a square lattice and one…

回溯加剪枝 #include <cstdio> #include <cstdlib> #include <cmath> #include <map> #include <set> #include <sstream> #include <string> #include <cstring> #include <algorithm> #include <iostream> #define…

题意: n*n的矩形阵(n<=5),由2*n*(n+1)根火柴构成,那么当中会有非常多诸如边长为1,为2...为n的正方形,如今能够拿走一些火柴,那么就会有一些正方形被破坏掉. 求在已经拿走一些火柴的情况下.还须要拿走至少多少根火柴能够把全部的正方形都破坏掉. 思路: 对于每一个位置遍历全部可能的边长,确定这个边长下的正方形的边相应的都是数字几,而且把正方形从1開始编号. 然后依据编号,把正方形和数字建边记录方便以下建图. 然后以火柴棍为行,正方形为列,建立dancing link 然后求解.…