题目链接:http://codeforces.com/problemset/problem/144/D 思路:首先spfa求出中心点S到其余每个顶点的距离,统计各顶点到中心点的距离为L的点,然后就是要统计在边上的点了,可以枚举边(这里边的数量最多也就100000条),对于枚举的某条边,如果它的其中某个端点到S的距离记过这条边,也就是满足一下这个条件:d1 + w == d2 || d2 + w == d1,那么边上符合要求的点最多只有一个,否则,就要判断d1,d2的关系,对于求出的边上的某个符合…

题目传送门 /* 最短路: 不仅扫描边,还要扫描点:点有两种情况,一种刚好在中点,即从u,v都一样,那么最后/2 还有一种是从u,v不一样,两种的距离都是l 模板错了,逗了好久:( */ #include <cstdio> #include <algorithm> #include <cstring> #include <cmath> #include <vector> #include <queue> using namespace…

题目链接:http://codeforces.com/problemset/problem/761/C C. Dasha and Password time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output After overcoming the stairs Dasha came to classes. She needed to w…

E https://codeforces.com/contest/1154/problem/E 题意 一个大小为n(1e6)的数组\(a[i]\)(n),两个人轮流选数,先找到当前数组中最大的数然后选择以这个数为半径k的所有数,问两个人的选数情况 题解 set维护剩下数的最大 链表维护左右第一个存在的数的位置 代码 #include<bits/stdc++.h> #define MAXN 200005 using namespace std; int n,k,a[MAXN],p[MAXN],L…

A. Currency System in Geraldion time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A magic island Geraldion, where Gerald lives, has its own currency system. It uses banknotes of several valu…

A. Flipping Game     time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Iahub got bored, so he invented a game to be played on paper. He writes n integers a1, a2, ..., an. Each of those intege…

B. Proper Nutrition time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vasya has n burles. One bottle of Ber-Cola costs a burles and one Bars bar costs b burles. He can buy any non-negative in…

Codeforces Round #633(Div.2) \(A.Filling\ Diamonds\) 答案就是构成的六边形数量+1 //#pragma GCC optimize("O3") //#pragma comment(linker, "/STACK:1024000000,1024000000") #include<bits/stdc++.h> using namespace std; function<void(void)> __…

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…