Pogram Konversi Nilai Mahasiswa Dalam C++

#include <cstdlib>
#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{  int nilai;
    cout<<"========================================================="<<endl;
    cout<<"                 PROGRAM KONVERSI NILAI MAHASISWA                 "<<endl;
    cout<<"========================================================="<<endl;
    cout<<"Masukkan nilai Mahasiswa : ";
    cin>>nilai;
    {
    if (nilai >= 80 && nilai <=100){
        cout<<"Nilai "<<nilai<<" = A"<<endl;
    }
    else if (nilai >= 65 && nilai <=79){
        cout<<"Nilai "<<nilai<<" = B"<<endl;
    }

    else if (nilai >= 55 && nilai <=64){
        cout<<"Nilai "<<nilai<<" = C"<<endl;
    }
    else if (nilai >= 40 && nilai <=54){
        cout<<"Nilai "<<nilai<<" = D"<<endl;
    }
    else{
        cout<<"Nilai "<<nilai<<" = E"<<endl;
    }
}
    system("pause");
    return 0;

}


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