Simple for() loop benchmark takes the same time with any loop bound

Question

I\'m willing to write a code that makes my CPU execute some operations and see how much time does he take to solve them. I wanted to make a loop going from i=0 to i<5000

Answer 1

Because of the body of the for loop:

i*434243;

which does nothing, so assuming you are compiling the code with optimization flags enabled, the compiler wipes that out.

Changing it to:

int a = i*434243;

would be likely be optimized out on anything else than -O0, so I wouldn't suggest it.

Moreover, this will lead to Undefined Behavior, because overflowing, since the constant value you are using is relatively big, as i continues to increment.

I suggest you do instead:

int a = i * i;
cout << a << "\n";