【输入输出格式】HDU-1202 The calculation of GPA

注解

1、注意输入输出格式，水题。

代码

#include <iostream>

using namespace std;

int gpa(double grade) {
    int gpa;
    int g[] = {0, 60, 70, 80, 90};
    for(int i=4; i>=0; i--) {
        if(grade>=g[i]) {
            gpa = i;
            break;
        }
    }
    return gpa;
}

int main() {

    int n;
    while(scanf("%d", &n)!=EOF) {
        double sumGrade = 0;
        double credit = 0;
        for(int i=0; i<n; i++) {
            double dou[n][2];
            scanf("%lf %lf", &dou[i][0], &dou[i][1]);
            if(dou[i][1]>=0) {
                credit += dou[i][0];
                sumGrade += dou[i][0] * gpa(dou[i][1]);
            }
        }
        if(credit>0) {
            double re = sumGrade/credit;
            printf("%.2lf\n", re);
        } else {
            printf("-1\n");
        }
    }

    return 0;
}

结果