am nevoie urgent de ajutor ex1,2

#include<bits/stdc++.h>
using namespace std;
double a, b, e;
int main ()
{
cin>>a>>b;
e=2*a+7-b;
cout<<e;
return 0;
}
#include<bits/stdc++.h>
using namespace std;
double a, b, c, ma;
int main ()
{
cin>>a>>b>>c;
ma=(a+b+c)/3;
cout<<ma;
return 0;
}