杭电1009 测试数据都对还是WA 新入ACM坑求解答啊：（

Question

#include <iostream>
#include <iomanip>
#include<algorithm>
#define MAX 1000
using namespace std;
struct room{
    int javabeen;
    int catfood;
    double price;
};
room a[MAX];
int M,N,n0,n1;
bool rule(room x,room y){
    return x.price<y.price;
}
int main(){
    while(cin>>M>>N && !(M==-1 && N==-1)){
        for(int i=0;i<N;i++){
            cin>>n0>>n1;
            a[i].javabeen=n0;
            a[i].catfood=n1;
            if(n0==0) a[i].price=-1; 
            a[i].price=(double)n1/n0; 
        }
        sort(a,a+N,rule);
            double get=0.0;
            for(int i=0;i<N;i++){
                if(a[i].price==-1) break;
                if(M>=a[i].catfood){
                    M-=a[i].catfood;
                    get+=a[i].javabeen;
                }
                else{
                    get=get+(double)M/a[i].price;
                    M=0;
                    break;
                }
            }
            cout<<fixed<<setprecision(3)<<get<<endl;
    }
    system ("pause");
    return 0;
}

Answer 1

http://blog.csdn.net/windowsshaking/article/details/7425625