D. Don't fear, DravDe is kind time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A motorcade of n trucks, driving from city «Z» to city «З», has approached a tunnel, known as Tunnel of Horror…
补一篇以前的扩展欧几里得的题,发现以前写错了竟然也过了,可能数据水??? 这个题还是很有意思的,和队友吵了两天,一边吵一边发现问题??? L. Knights without Fear and Reproach http://codeforces.com/gym/100812/problem/L time limit per test 2.0 s memory limit per test 256 MB input standard input output standard output Th…
题目传送门:http://codeforces.com/problemset/problem/28/D 题意:给你$N$个物品,每个物品有其价格$P_i$,之前必须要买的物品价格和$L_i$,之后必须要买的物品价格和$R_i$和价值$W_i$.试给出一种物品的选择方案,使得满足所有选择的物品的条件且选择物品的价值和最大(物品的选择顺序必须要与原来的顺序相同).$N \leq 10^5 , P , L , R \leq 10^5 , W \leq 10^4$ 像背包DP,所以就是背包DP(雾 我们…
题目链接:点击打开链接 给定n表示有n个格子 以下每一个格子为O的概率是多少. 对于一段连续 x 个O的价值就是 x*x ; 问: 获得的价值的期望是多少. 思路: 把公式拆一下.. #include <cstdio> const int N = 100005; double dp[N][2], p[N]; int main(){ int n; scanf("%d", &n); for(int i = 1; i <= n; i ++) { scanf(&quo…
http://codeforces.com/problemset/problem/743/D 题意:求最大两个的不相交子树的点权和,如果没有两个不相交子树,那么输出Impossible. 思路:之前好像也做过这种类型的题目啊,知道是树形DP,但是不知道怎么保证两个不相交.看别人代码之后, 在DFS回溯的时候, void dfs(int u, int fa) { sum[u] = w[u]; for(int i = head[u]; ~i; i = edge[i].nxt) { int v = e…
Coloring Trees Problem Description: ZS the Coder and Chris the Baboon has arrived at Udayland! They walked in the park where n trees grow. They decided to be naughty and color the trees in the park. The trees are numbered with integers from 1 to n fr…
题目链接: http://codeforces.com/problemset/problem/268/E E. Playlist time limit per test 1 secondmemory limit per test 256 megabytes 问题描述 Manao's friends often send him new songs. He never listens to them right away. Instead, he compiles them into a play…
题目链接: http://codeforces.com/contest/464/problem/C J. Substitutes in Number time limit per test 1 secondmemory limit per test 256 megabytes 问题描述 Andrew and Eugene are playing a game. Initially, Andrew has string s, consisting of digits. Eugene sends A…
Hard problem 题目链接: http://codeforces.com/contest/706/problem/C Description Vasiliy is fond of solving different tasks. Today he found one he wasn't able to solve himself, so he asks you to help. Vasiliy is given n strings consisting of lowercase Engl…
D. Fox And Jumping 题目连接: http://codeforces.com/contest/510/problem/D Description Fox Ciel is playing a game. In this game there is an infinite long tape with cells indexed by integers (positive, negative and zero). At the beginning she is standing at…
B. Maximum Submatrix 2 Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/problemset/problem/375/B Description You are given a matrix consisting of digits zero and one, its size is n × m. You are allowed to rearrange its rows. What is…
B. Strip Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/487/problem/B Description Alexandra has a paper strip with n numbers on it. Let's call them ai from left to right. Now Alexandra wants to split it into some pieces (p…
E. LIS of Sequence Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/486/problem/E Description The next "Data Structures and Algorithms" lesson will be about Longest Increasing Subsequence (LIS for short) of a sequence.…
D. Duff in Beach Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/588/problem/D Description While Duff was resting in the beach, she accidentally found a strange array b0, b1, ..., bl - 1 consisting of l positive integers. Th…
F. Bulbo Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/575/problem/F Description Bananistan is a beautiful banana republic. Beautiful women in beautiful dresses. Beautiful statues of beautiful warlords. Beautiful stars in…
Problem K. Kitchen Robot Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100610 Description Robots are becoming more and more popular. They are used nowadays not only in manufacturing plants, but also at home. One programmer wit…
B. Modulo Sum Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/577/problem/B Description You are given a sequence of numbers a1, a2, ..., an, and a number m. Check if it is possible to choose a non-empty subsequence aij such…
Problem Codeforces #548 (Div2) - D.Steps to One Time Limit: 2000 mSec Problem Description Input The first and only line contains a single integer mm (1≤m≤100000,1≤m≤100000). Output Print a single integer — the expected length of the array aa writte…