题目链接:http://codeforces.com/problemset/problem/148/D 题意: 一个袋子中有w只白老鼠,b只黑老鼠. 公主和龙轮流从袋子里随机抓一只老鼠出来,不放回,公主先拿. 公主每次抓一只出来.龙每次在抓一只出来之后,会随机有一只老鼠跳出来(被龙吓的了...). 先抓到白老鼠的人赢.若两人最后都没有抓到白老鼠,则龙赢. 问你公主赢的概率. 题解: 表示状态: dp[i][j] = probability to win(当前公主先手,公主赢的概率) i:剩i只白…

http://codeforces.com/problemset/problem/148/D 题目大意: 原来袋子里有w只白鼠和b只黑鼠 龙和王妃轮流从袋子里抓老鼠.谁先抓到白色老鼠谁就赢. 王妃每次抓一只老鼠,龙每次抓完一只老鼠之后会有一只老鼠跑出来. 每次抓老鼠和跑出来的老鼠都是随机的. 如果两个人都没有抓到白色老鼠则龙赢.王妃先抓. 问王妃赢的概率. (0 ≤ w, b ≤ 1000). 题解: 其中第一行表示为王妃拿到的白色老鼠,自然是直接退出了 第二行表示为王妃拿到了黑色老鼠,但是因为…

题目链接:http://codeforces.com/problemset/problem/148/D 题意: 原来袋子里有w仅仅白鼠和b仅仅黑鼠 龙和王妃轮流从袋子里抓老鼠. 谁先抓到白色老师谁就赢. 王妃每次抓一仅仅老鼠.龙每次抓完一仅仅老鼠之后会有一仅仅老鼠跑出来. 每次抓老鼠和跑出来的老鼠都是随机的. 假设两个人都没有抓到白色老鼠则龙赢.王妃先抓. 问王妃赢的概率. 解析: 设dp[i][j]表示如今轮到王妃抓时有i仅仅白鼠,j仅仅黑鼠.王妃赢的概率 明显 dp[0][j]=0,0<=j…

题意:给你w个白色小鼠和b个黑色小鼠,把他们放到袋子里,princess先取,dragon后取,princess取的时候从剩下的当当中任意取一个,dragon取得时候也是从剩下的时候任取一个,但是取完之后会随机跳出来一个.取到每个小鼠的概率是一样的,跳出的也是一样的.先取到白色的小鼠赢,问最后princess能赢的概率. 思路:概率dp,如果把princess能赢的分成两种情况,那么这个题就是递推了,我是用记忆化搜索写的.首先,用dp[i][j]表示袋子当中还有i个白色的,j个黑色的prince…

D. Bag of mice time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The dragon and the princess are arguing about what to do on the New Year's Eve. The dragon suggests flying to the mountains t…

D. Bag of mice time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The dragon and the princess are arguing about what to do on the New Year's Eve. The dragon suggests flying to the mountains t…

D. Bag of mice time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The dragon and the princess are arguing about what to do on the New Year's Eve. The dragon suggests flying to the mountains t…

D. Bag of mice time limit per test 2 seconds memory limit per test 256 megabytes Promblem description   The dragon and the princess are arguing about what to do on the New Year's Eve. The dragon suggests flying to the mountains to watch fairies danci…

time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The dragon and the princess are arguing about what to do on the New Year's Eve. The dragon suggests flying to the mountains to watch fairies…

http://codeforces.com/problemset/problem/148/D 题意:w个白b个黑,公主和龙轮流取,公主先取,等概率取到一个.当龙取完后,会等概率跳出一只.(0<=w, b<=1000) #include <bits/stdc++.h> using namespace std; int n, m; const int N=1005; double d[N][N][2]; int main() { scanf("%d%d", &…