How to write a program on how many seconds in a day?please help?

Answer 1

cout << 24 * 60 * 60;

Answer 2

There are 60 seconds in a minute and 60 minutes in an hour and 24 hours in a day. So:
int secondsInDay = 60 * 60 * 24;

Answer 3

For the current second count:

#include <ctime>
#include <iostream>

int main()
{
std::cout << std::time(0) % (24 * 60 *60);
}

Answer 4

iOStream ??