HDOJ

HDOJ 1.3.1 FatMouse' Trade_

WA了 待调

using namespace std;
struct st{
    double j; double f; double x;
    bool operator < (const struct st&a )const{
        return x > a.x;
    }
}a[2000];
double res = 0.0; int p = 1;
int main() {
    while(1){
        double M; int N ; cin >> M >> N;
        res = 0.0 ; p = 1;
        if(N == -1 ) break;
        for(int i =1 ;  i <= N ; i++){
            cin >> a[i].j >> a[i].f ;
            if( a[i].f ==  0 ) a[i].x = 100001.0;
            else a[i].x = (double)a[i].j * 1.0  / (double) a[i].f;
        }
        sort(a + 1, a+ 1 + N);
        for(int i =  1;  i <= N ; i++){
            if(a[i].f <= M){
                res += a[i].j;
                M -= a[i].f;
            }else{
                res += (double)M * 1.0 * a[i].x  ;
                break;
            }
        }
        printf("%.3lf\n", res);
     }
    return 0;
}