这题用并查集来做,判断什么时候形成了环即判断什么时候加入的线段两个端点原先是属于同一集合的.对于一个点,有两个坐标x,y,不好做并查集操作,于是要用map来存储,即做成map<node,int>形式,每加入一条线段,如果没有出现过这一个/两个端点,则赋此条线段一个/两个端点一个类型,然后找他的两个端点是否原先在同一个集合即可. 代码: #include <iostream> #include <cstdio> #include <map> using nam…

题意: 判断给出的线段是否组成了多边形. Solution: 简单题,并查集+hash 这里用map实现 code #include <iostream> #include <cstdio> #include <utility> #include <map> using namespace std; typedef pair<int, int> ii; map<ii, int> f; int fa[400009]; int n, xa…

本解题报告 乱抄,乱写,随性随心,不喜多喷! SGU 142: 思路:一个string的字串不会超过2^20个,我们枚举出来就好了. 我出错点:数组RE #include<stdio.h> #include<math.h> #include<algorithm> #include<string.h> #include<string> #include<iostream> #include<set> #include<…

#include<bits/stdc++.h> #define de(x) cout<<#x<<"="<<x<<endl; #define dd(x) cout<<#x<<"="<<x<<" "; #define rep(i,a,b) for(int i=a;i<(b);++i) #define repd(i,a,b) for(int…

SGU 解题报告(持续更新中...Ctrl+A可看题目类型): SGU101.Domino(多米诺骨牌)------------★★★type:图 SGU102.Coprimes(互质的数) SGU103.TrafficLights(交通灯)---------★★type:图 SGU104.LittleShopofFlowers(小花店)---★type:DP SGU105.Div3(整除3) SGU106.TheEquation(方程)-------------★type:数论 SGU107.…

http://acm.sgu.ru/problemset.php?contest=0&volume=1 101 Domino 欧拉路 102 Coprime 枚举/数学方法 103 Traffic Lights 最短路 104 Little Shop of Flowers 动态规划 105 Div 3 找规律 106 The Equation 扩展欧几里德 107 987654321 Problem 找规律 108 Self-numbers II 枚举+筛法递推 109 Magic of Dav…

水概率....SGU里难得的水题.... 495. Kids and Prizes Time limit per test: 0.5 second(s)Memory limit: 262144 kilobytes input: standardoutput: standard ICPC (International Cardboard Producing Company) is in the business of producing cardboard boxes. Recently the…

sgu 101 - Domino Time Limit:250MS     Memory Limit:4096KB     64bit IO Format:%I64d & %I64u Description Dominoes – game played with small, rectangular blocks of wood or other material, each identified by a number of dots, or pips, on its face. The bl…

http://acm.sgu.ru/problem.php?contest=0&problem=495 题意:N个箱子M个人,初始N个箱子都有一个礼物,M个人依次等概率取一个箱子,如果有礼物则拿出礼物放回盒子,如果没有礼物则不操作.问M个人拿出礼物个数的期望.(N,M<=100000) #include <cstdio> using namespace std; double mpow(double a, int n) { double r=1; while(n) { if(n&…

题目链接:http://acm.sgu.ru/problem.php?contest=0&problem=455 Due to the slow 'mod' and 'div' operations with int64 type, all Delphi solutions for the problem 455 (Sequence analysis) run much slower than the same code written in C++ or Java. We do not gua…