题目链接 2了,差点就A了...这题真心不难,开始想的就是暴力spfa就可以,直接来了一次询问,就来一次的那种,TLE了,想了想,存到栈里会更快,交又TLE了..无奈C又被cha了,我忙着看C去了...这题,是我一个地方写错了..top = 0的时候会死循环吗?貌似不会把,反正我加了这个判断,就A了,可能优化了一下把. #include <cstring> #include <cstdio> #include <string> #include <iostream…

注意题目的数字最大是7 而能整除的只有 1,2,3,4,6,故构成的组合只能是1,2,4 或1,2,6或1,3,6,故分别统计1,2,3,4,6的个数,然后再分配 #include <iostream> #include <vector> #include <algorithm> #include <string> using namespace std; int main(){ int n; cin >> n ; vector<int&g…

A.Xenia and Divisors 题意:给定N个数,每个数的取值范围为1-7,N是3的倍数,判定是否能够恰好将N个数分成若干三元组,使得一个组中的元素a,b,c满足 a < b < c 并且 a|b && b|c(整除). 分析:满足这种条件的三元组只有[1, 2, 4], [1, 2, 6], [1, 3, 6]因此如果有5或者是7肯定是不行的,然后是1的个数要等于4和6的个数之和,最后就是2的数量必须4的数量. #include <cstdlib> #i…

B. Xenia and Spies time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Xenia the vigorous detective faced n (n ≥ 2) foreign spies lined up in a row. We'll consider the spies numbered from 1 to…

C. Cupboard and Balloons time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A girl named Xenia has a cupboard that looks like an arc from ahead. The arc is made of a semicircle with radius r …

把 'O' 看成 'X',然后枚举它的四个方向看看是否能放,然后枚举 $2^4$ 种可能表示每种方向是否放了,放了的话就标成 'X',就相当于容斥,对于新的图去dp. dp就是铺地砖,行用二进制来表示是否放了砖块. #include <bits/stdc++.h> ; ; ][] = {{, -}, {, }, {, }, {-, }}; << ], n, sx, sy; ][N]; ][N], mp[][N]; void M(int &a) { if (a >= M…

Codeforces Round #515 (Div. 3) #include<bits/stdc++.h> #include<iostream> #include<cstdio> #include<cstdlib> #include<cstring> #include<cmath> #include<algorithm> #include<queue> #include<vector> #incl…

Codeforces Round #366 (Div. 2) A I hate that I love that I hate it水题 #I hate that I love that I hate it n = int(raw_input()) s = "" a = ["I hate that ","I love that ", "I hate it","I love it"] for i in ran…

Codeforces Round #354 (Div. 2) Problems     # Name     A Nicholas and Permutation standard input/output 1 s, 256 MB    x3384 B Pyramid of Glasses standard input/output 1 s, 256 MB    x1462 C Vasya and String standard input/output 1 s, 256 MB    x1393…

直达–>Codeforces Round #368 (Div. 2) A Brain’s Photos 给你一个NxM的矩阵,一个字母代表一种颜色,如果有”C”,”M”,”Y”三种中任意一种就输出”#Color”,如果只有”G”,”B”,”W”就输出”#Black&White”. #include <cstdio> #include <cstring> using namespace std; const int maxn = 200; const int INF =…