478A codeforces solution in cpp

 

478A codeforces solution in cpp

by ujjal roy

#include<bits/stdc++.h>

using namespace std;

main()

{

    int c1,c2,c3,c4,c5,sum=0;

    cin>>c1>>c2>>c3>>c4>>c5;

    sum=c1+c2+c3+c4+c5;

    if(sum!=0&&sum%5==0) cout<<sum/5<<endl;

    else cout<<"-1"<<endl;

    return 0;

}