hdu2955 概率dp

//dp[i]保存盗取i的钱时不被抓的最大概率//dp[i]=max(dp[i],dp[i-W[j]]*P[j]),W[j]表示这家银行所拥有的的钱,P[j]表示在这家银行不被抓的概率#include<iostream>#include<algorithm>using namespace std;const int maxn = 107;int D[maxn];double B[maxn];double dp[maxn * 100];//dp[i]定义为得到i的钱时的最高生存概率bool vis[maxn * 100];int main(){    int T;    cin >> T;    while (T--)    {        memset(vis, 0, sizeof(vis));        for (int i = 0; i < maxn * 100; i++)        {            dp[i] = 0.0;        }        double P;        int N;        cin >> P >> N;        P = 1 - P;        double p;        for (int i = 1; i <= N; i++)        {            cin >> D[i] >> p;            B[i] = 1 - p;        }        dp[0] = 1;        vis[0] = 1;        int maxloc = 0;        for (int i = 1; i <= N; i++)        {            for (int j = maxloc; j >= 0; j--)            {                if (vis[j])                {                    int k = j + D[i];                    maxloc = max(k, maxloc);                    vis[k] = 1;                    dp[k] = max(dp[k], dp[j] * B[i]);                }            }        }        int ans = 0;        for (int i = maxloc; i >=0; i--)        {            if (vis[i] && dp[i] >= P)            {                ans = i;                break;            }        }        cout << ans << endl;    }    return 0;;}