LightOJ 1104 - Birthday Paradox【概率】

题目链接：http://www.lightoj.com/volume_showproblem.php?problem=1104
题意：生日驳论，求最小满足条件的人数
代码：

#include <stdio.h>#include <iostream>#include <string.h>#include <algorithm>#include <bitset>#include <math.h>#include <ctype.h>#include <time.h>#include <queue>#include <map>#include <set>using namespace std;int t;int n;int dp[100010];int main(){    cin >> t;    for (int ca = 1; ca <= t; ca++)    {        memset(dp,0,sizeof(dp));        cin >> n;        cout << "Case " << ca << ": ";        if (n == 1)            cout << 1 << endl;        else        {            double ans = 1.0;            int i;            for ( i = 1; i <= n; i++)            {                ans *= ((n - i)*1.0 / n);                if (ans <= 0.5)                    break;            }            cout << i << endl;        }    }    return 0;}