D. Jerry's Protest time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andr…

题意: 一个袋子里装了n个球,每个球都有编号.甲乙二人从每次随机得从袋子里不放回的取出一个球,如果甲取出的球比乙取出的球编号大则甲胜,否则乙胜.保证球的编号xi各不相同.每轮比赛完了之后把取出的两球放回.求甲在前两轮比赛胜利,乙在最后一轮比赛胜利的情况下,乙所有球的和大于甲所有球的和概率. 其中 2<=n<=2000  1<=xi<=5000 思路: 从xi的范围入手,记录某一轮中两个人的差值,然后再求解出一个后缀和,代表某轮比赛中其中一人比另一人大x以上的概率.这样枚举前两轮的差…

计算前两盘A赢,最后一盘B赢的情况下,B获得的球的值总和大于A获得的球总和值的概率. 存储每一对球的差值有几个,然后处理一下前缀和,暴力枚举就好了...... #include<cstdio> #include<cstring> #include<cmath> #include<string> #include<vector> #include<queue> #include<algorithm> #include<…

D. Jerry's Protest 题目连接: http://www.codeforces.com/contest/626/problem/D Description Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andrew and Jerry draw randomly without replaceme…

Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andrew and Jerry draw randomly without replacement from a jar containing n balls, each labeled with a distinct positive integer. With…

Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andrew and Jerry draw randomly without replacement from a jar containing n balls, each labeled with a distinct positive integer. With…

Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andrew and Jerry draw randomly without replacement from a jar containing n balls, each labeled with a distinct positive integer. With…

在家补补题   模拟 A - Robot Sequence #include <bits/stdc++.h> char str[202]; void move(int &x, int &y, char ch) { if (ch == 'U') x--; if (ch == 'D') x++; if (ch == 'L') y--; if (ch == 'R') y++; } int main(void) { int n; scanf ("%d", &…

D. Jerry's Protest time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andr…

Codeforces 718A Efim and Strange Grade 程序分析 jerry的程序 using namespace std; typedef long long ll; string buf; int i; void up(int at) { at--; if (at < 0) { buf = '1' + buf; i++; return; } if (buf[at] == '.') at--; buf[at]++; if (buf[at] == '9'+1) { buf[…