Codeforces Round #599 (Div. 2) D. 0-1 MST Description Ujan has a lot of useless stuff in his drawers, a considerable part of which are his math notebooks: it is time to sort them out. This time he found an old dusty graph theory notebook with a descr…

题:https://codeforces.com/contest/1243/problem/D 分析:找全部可以用边权为0的点连起来的全部块 然后这些块之间相连肯定得通过边权为1的边进行连接 所以答案就是这些块的总数-1: #include<bits/stdc++.h> using namespace std; typedef long long ll; #define pb push_back ; set<int>s,g[M]; int vis[M]; void bfs(int…

久违的写篇博客吧 A. Maximum Square 题目链接:https://codeforces.com/contest/1243/problem/A 题意: 给定n个栅栏,对这n个栅栏进行任意排序,问可形成的最大正方形面积是多少 分析: 水题. 先排个序 , 然后暴力枚举正方形边长就可以了 #include<bits/stdc++.h> #define ios std::ios::sync_with_stdio(false) #define sd(n) scanf("%d&qu…

这题写起来真的有点麻烦,按照官方题解的写法 先建图,然后求强连通分量,然后判断掉不符合条件的换 最后做dp转移即可 虽然看起来复杂度很高,但是n只有15,所以问题不大 #include <iostream> #include <fstream> #include <vector> #include <set> #include <map> #include <bitset> #include <algorithm> #in…

排序+暴力 #include<bits/stdc++.h> using namespace std; #define int long long #define N 1005000 int arr[N]; signed main(){ int _,n; cin>>_; while(_--){ cin>>n; ;i<=n;i++) cin>>arr[i]; sort(arr+,arr++n); ; ;i<=n;i++){ ; ; ;j--){ if…

难题不会啊…… 我感觉写这个的原因就是因为……无聊要给大家翻译题面 A. Maximum Square 简单题意: 有$n$条长为$a_i$,宽为1的木板,现在你可以随便抽几个拼在一起,然后你要从这一大块木板中裁出一块最大的正方形. $1 \leq a_i \leq n \leq 1000$ 多测,$T \leq 10$ 给个官网的图: 直接排序然后扫就行了,这数据范围是不是让你想什么神奇东西了? #include <algorithm> #include <iostream> #…

Ujan has been lazy lately, but now has decided to bring his yard to good shape. First, he decided to paint the path from his house to the gate. The path consists of nn consecutive tiles, numbered from 11 to nn. Ujan will paint each tile in some color…

This problem is different from the easy version. In this version Ujan makes at most 2n2n swaps. In addition, k≤1000,n≤50k≤1000,n≤50 and it is necessary to print swaps themselves. You can hack this problem if you solve it. But you can hack the previou…

题意:就是给你一个n,然后如果  n mod | i - j | == 0  并且 | i - j |>1 的话,那么i 和 j 就是同一种颜色,问你最大有多少种颜色? 思路: 比赛的时候,看到直接手推,发现有点东西,直接打表找出了规律 —— 如果 n的质因子只有一个,那么总数就是 那个 质因子.其它都为 1. 今天上课的时候无聊,还是试着推了一下原理. 1.如果一个数只有一个质因子 x ,那么  n-x .n-2x.n-3x ……等等全为一种颜色,也就是说每隔 x个就是同种颜色,这样的话就是有…

C. Sum Balance Ujan has a lot of numbers in his boxes. He likes order and balance, so he decided to reorder the numbers. There are…