OJ-Problems-Source/HDOJ/4802_autoAC.cpp
2016-09-10 11:32:44 +08:00

34 lines
712 B
C++

#include<stdio.h>
#include<string.h>
#include<string>
#include<iostream>
#include<map>
#include<algorithm>
using namespace std;
map<string,double>m;
double s,sum1,sum2;
string op;
int n;
int main()
{
m["A"]=4.0,m["A-"]=3.7,m["B+"]=3.3,m["B"]=3.0;
m["B-"]=2.7,m["C+"]=2.3,m["C"]=2.0,m["C-"]=1.7;
m["D"]=1.3,m["D-"]=1.0,m["F"]=0;
while(cin>>n)
{
sum1=0,sum2=0;
for(int i=0;i<n;i++)
{
cin>>s>>op;
if(op=="P"||op=="N")
continue;
sum2+=s;
sum1+=s*m[op];
}
if(sum2==0)
printf("0.00\n");
else
printf("%.2lf\n",sum1/sum2);
}
}