POJ 3905 Perfect Election id=3905" target="_blank" style="">题目链接 思路:非常裸的2-sat,就依据题意建边就可以 代码: #include <cstdio> #include <cstring> #include <cstdlib> #include <vector> #include <algorithm> using nam…

Perfect Election Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 438   Accepted: 223 Description In a country (my memory fails to say which), the candidates {1, 2 ..., N} are running in the parliamentary election. An opinion poll asks th…

2-SAT 裸题,搞之 #include<cstdio> #include<cstring> #include<cmath> #include<stack> #include<vector> #include<algorithm> using namespace std; +; int N,M; ],s2[]; stack<int>S; vector<int>G[maxn]; vector<int>…

题意:有N个人参加选举,有M个条件,每个条件给出:i和j竞选与否会只要满足二者中的一项即可.问有没有方案使M个条件都满足. 分析:读懂题目即可发现是2-SAT的问题.因为只要每个条件中满足2个中的一个即可,因此将人i拆成 点i表示不竞选,和点i+N表示竞选,根据合取式的满足条件建图跑Tarjan. 最后检查每个i与i+N是否在同一强连通分量中. #include<stdio.h> #include<iostream> #include<algorithm> #inclu…

Perfect Election Time Limit: 5000MS         Memory Limit: 65536K Total Submissions: 964         Accepted: 431 Description In a country (my memory fails to say which), the candidates {1, 2 ..., N} are running in the parliamentary election. An opinion…

POJ 3398 Perfect Service(树型动态规划,最小支配集) Description A network is composed of N computers connected by N − 1 communication links such that any two computers can be communicated via a unique route. Two computers are said to be adjacent if there is a com…

1.链接地址: http://bailian.openjudge.cn/practice/2810/ http://bailian.openjudge.cn/practice/1543/ http://poj.org/problem?id=1543 2.题目: Perfect Cubes Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 13190   Accepted: 6995 Description For hundr…

题目链接:http://poj.org/problem?id=3398 这题可以用两种上述讲的两种算法解:http://www.cnblogs.com/whatbeg/p/3776612.html 第一种,贪心算法: 贪心算法直接套一个最小支配集模板就可以了,我不能证明这样是正确的,但是能AC 代码: #include <iostream> #include <cstdio> #include <cstring> #include <cmath> #incl…

Perfect Cubes Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 14901   Accepted: 7804 Description For hundreds of years Fermat's Last Theorem, which stated simply that for n > 2 there exist no integers a, b, c > 1 such that a^n = b^n + c…

题目链接: https://cn.vjudge.net/problem/POJ-1730 题目描述: We say that x is a perfect square if, for some integer b, x = b 2. Similarly, x is a perfect cube if, for some integer b, x = b 3. More generally, x is a perfect pth power if, for some integer b, x =…