之前只从开头读入，没想到还能在中间读入

\n老是忘记加

#include<cstdio>
#include<iostream>
using namespace std;
int main()
{
    double n1,n2,n3,n4;
    cin>>n1>>n2>>n3>>n4;
    double x=(n1*2+n2*3+n3*4+n4)/10;
    printf("Media: %.1lf\n",x);
    if(x>=7) cout<<"Aluno aprovado."<<endl;
    else if(x<5) cout<<"Aluno reprovado."<<endl;
    else
    {
        cout<<"Aluno em exame."<<endl;
        double y,z;
        cin>>y;
        printf("Nota do exame: %.1lf\n",y);
        z=(x+y)/2;
        if(z>=5) cout<<"Aluno aprovado."<<endl;
        else cout<<"Aluno reprovado."<<endl;
        printf("Media final: %.1lf\n",z);
    }
    return 0;
}