C++ 代码

#include <cstdio>
#include <iostream>
using namespace std;

int main()
{
    double a,b,c,d,x;
    scanf("%lf%lf%lf%lf",&a,&b,&c,&d);
    x = (a*2.0+b*3.0+c*4.0+d) / 10.0;
    printf("Media: %.1lf\n",x);
    if (x >= 7) printf("Aluno aprovado.\n");
    else if (x < 5) printf("Aluno reprovado.\n");
    else if (x >= 5 && x < 7)
    {
        printf("Aluno em exame.\n");
        double y,z;
        scanf("%lf",&y);
        printf("Nota do exame: %.1lf\n",y);
        z = (x+y) / 2;
        if (z >= 5) printf("Aluno aprovado.\n");
        else printf("Aluno reprovado.\n");
        printf("Media final: %.1lf",z);
    }
    return 0;
}