显然是不可能交叉取钥匙的,于是把钥匙和人都按坐标排序就可以DP了 钥匙可以不被取,于是f[i][j]表示前i个钥匙被j个人拿的时间 f[i][j]=min(f[i-1][j],max(f[i-1][j-1],abs(b[i]-a[j])+abs(P-b[i])); #include<bits/stdc++.h> #define ll long long using namespace std; ,inf=2e9; int n,k,p; ],f[maxn*][maxn]; void read(i…

题目要求符合以下条件的最大的d 化简得 注意到 最多只有2*sqrt(a[i]-1)种取值,也就是一共最多有n*sqrt(10^19)种取值,于是枚举一下d,计算出符合上上式的最大的d更新答案,然后d跳跃到下一个取值 效率O(n²sqrt(10^9)) #include<bits/stdc++.h> #define ll long long using namespace std; ,inf=1e9; ll n,k,ans,r; ll a[maxn]; void read(ll &k)…

题目地址:http://codeforces.com/contest/456/problem/C 脑残了. .DP仅仅DP到了n. . 应该DP到10w+的. . 代码例如以下: #include <iostream> #include <cstdio> #include <string> #include <cstring> #include <stdlib.h> #include <math.h> #include <cty…

题目:http://codeforces.com/problemset/problem/429/B 第一个人初始位置在(1,1),他必须走到(n,m)只能往下或者往右 第二个人初始位置在(n,1),他必须走到(1,m)只能往上或者往右 每个点都有个权值,要求两个人中间相遇一次且只有一次,相遇的那个点的权值不算,两个人的速度可以不一样,然后求出最大值是多少 思路:他的要求是相遇一次且只有一次,那么画几个图其实就只有两个情况了(这图是借了一位大佬的,[小声bb]) 既然知道了这个图分为了这四个区域,…

Office Keys time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There are n people and k keys on a straight line. Every person wants to get to the office which is located on the line as well.…

这题做得比较复杂..应该有更好的做法 题目大意: 有一个括号序列,可以对其进行两种操作: ·        向里面加一个括号,可以在开头,在结尾,在两个括号之间加. ·        对当前括号序列进行循环移动,即把最后一个括号拿到开头来. 上述两种操作可以做任意次,要求添加最少的括号使得原序列变成一个合法括号序列.如果有多种可能,输出字典序最小的那一个."(" < ")". 题解: 首先计算左括号和右括号的数量,可以知道,不妨假设左括号的数量大于右括号 那么…

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…

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/455/A A. Boredom time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Alex doesn't like boredom. That's why whenever he gets bored, he comes up with…

This is an interactive problem. Remember to flush your output while communicating with the testing program. You may use fflush(stdout) in C++, system.out.flush() in Java, stdout.flush() in Python or flush(output) in Pascal to flush the output. If you…