题意:
计算GPA,输入一个数字和一个字符串,用 数字×字符串对应的数值
思路:
用map对应数值,要注意的是字符串为P或者N的时候,不计入结果
代码:
#include<iostream>
#include<string>
#include<cstring>
#include<cstdio>
#include<map>
using namespace std;
map<string, double> mp;
int main() {
mp["A"] = 4.0;
mp["A-"] = 3.7;
mp["B+"] = 3.3;
mp["B"] = 3.0;
mp["B-"] = 2.7;
mp["C+"] = 2.3;
mp["C"] = 2.0;
mp["C-"] = 1.7;
mp["D"] = 1.3;
mp["D-"] = 1.0;
mp["F"] = 0.0;
int t;
while (~scanf("%d", &t)) {
double x, ans = 0.0, index = 0.0;
string str;
for (int i = 1; i <= t; i++) {
cin >> x >> str;
if (str == "P" || str == "N") continue;
ans += x * mp[str];
index += x;
}
if (index == 0) printf("0.00
");
else printf("%.2lf
", ans / index);
}
return 0;
}