++ question for more inderstant

[haloAE]

#include<iostre am>
using namespace std;
int main()
{

int a = 5;
int b = 5;
int c = 5;
int d = 5;
int e = 5;
int f = 5;
a = a++ + a++;
b = b++ + ++b;
c = ++c + c++;
d = ++d + ++d;
e = e++;
f = f + ++f;
cout << a++ << endl;
cout << ++b << endl;
cout << ++a << endl;
cout << c++ << endl;
cout << ++d << endl;
cout << d++ << endl;
cout << ++c << endl;
cout << ++f << endl;
return 0;
}

[weaknessforcats]

Not good:

a = a++ + a++;
 b = b++ + ++b;
 c = ++c + c++;
 d = ++d + ++d;

You are allowed to change the value of a variable only once in a statement.

The compiler is free to calculate the value of the variables in any order. Maybe left-to-right. Maybe right-to-left.

This code is called indeterminate. The same program compiled with different compilers can yield different results. Or maybe not.

Don't do this.