/*"To handle cases where the value of a "variable" that is initialized with a value that is not known at compile time but never changes after initialization, C++ offers a second form of costant (a const)"*/

constexpr int max = 100;

void use(int n)
{
constexpr int c1 = max+7; //OK: c1 is 107
const int c2 = n+7; //OK, but don't try to change the value off c2
//...
c2 = 7; //error: c2 is a const
}