1202.cpp

杭电 acm部分代码 有兴趣的可以下载 谢谢

#include<iostream>
#include<cstdio>
using namespace std;
double mark[50000];
double scor[50000];
void main()
{
    double total,full;
    int    n,   i    ,temp;
    while(cin>>n){
        total = 0;
        full  = 0;
        for(i = 0;i < n;i++){
            cin>>scor[i]>>mark[i];
            if(mark[i] != -1){
                total += scor[i];
                if(mark[i] >= 60){
                    if(mark[i] == 100)
                        full += 4*scor[i];
                    else{
                        temp =  mark[i]-50;
                        full += temp/10*scor[i];
                    }
                }
            }
        }
        if(total > 0)
            printf("%.2lf\n",full/total);
        else if(total == 0)
            cout<<"-1"<<endl;
    }
}