hdu 1203 01背包

转化一下问题：求一个offer也拿不到的最小概率。

每个学校有个花费和概率，很显然是01背包问题。

#include <cstdio>
using namespace std;

const int N = 10001;
const double eps = 1e-8;
double f[N];
int n, m;

double min( double a, double b )
{
    if ( a + eps < b ) return a;
    return b;
}

int main ()
{
    while ( scanf("%d%d", &n, &m) != EOF )
    {
        if ( n == 0 && m == 0 ) break;
        for ( int i = 0; i <= n; i++ )
        {
            f[i] = 1.0;
        }
        for ( int i = 0; i < m; i++ )
        {
            int cost;
            double p;
            scanf("%d%lf", &cost, &p);
            p = 1 - p;
            for ( int j = n; j >= cost; j-- )
            {
                f[j] = min( f[j], f[j - cost] * p );
            }
        }
        f[n] = ( 1.0 - f[n] ) * 100.0;
        printf("%.1lf%%
", f[n]);
    }
    return 0;
}