sleep() function in c++

Question

Why when I put the sleep(40); in my C++ program it says it's wrong.

Answer 1

You'll need to include the right header file:

#include <unistd.h>

But this is as C code. There are better ways to do this in C++. Check this out for various ways on how to sleep in C/C++ https://www.geeksforgeeks.org/sleep-function-in-cpp/