HDU 2955 Robberies --01背包变形

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;
#define N 10007

int c[102];
double w[102],dp[N];  //dp[i]:抢劫到i块钱成功逃跑的概率

int main()
{
    int t,n,i,sum,v,V;
    double Vf;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%lf%d",&Vf,&n);
        Vf = 1 - Vf;
        V = 0;
        for(i=1;i<=n;i++)
        {
            scanf("%d %lf",&c[i],&w[i]);
            w[i] = 1 - w[i];
            V += c[i];
        }
        memset(dp,0,sizeof(dp));
        dp[0] = 1.0;  //抢到0块钱逃跑概率为1.0
        for(i=1;i<=n;i++)
        {
            for(v=V;v>=c[i];v--)
                dp[v] = max(dp[v],dp[v-c[i]]*w[i]);
        }
        for(i=V;i>=0;i--)
        {
            if(dp[i] >= Vf)
                break;
        }
        printf("%d\n",i);
    }
    return 0;
}