#include <iostream>
#include <cstdlib>
using namespace std;

/*
    Move a time forward by a given number of seconds.
    The function modifies the variables passed to it.
*/

void travel(int& hour, int& minute, int& second, int deltaSeconds)
{
    second += deltaSeconds;

    minute += second / 60;
    second %= 60;

    hour += minute / 60;
    minute %= 60;

    hour %= 24;
}

int main()
{
    int hour   {18};
    int minute {0};
    int second {0};

    cout << "How many seconds forward do you want to go from 6:00:00 p.m.? ";
    int delta {0};
    cin >> delta;

    if (!cin)
    {
        cerr << "Invalid input.\n";
        return EXIT_FAILURE;
    }

    travel(hour, minute, second, delta);

    cout << "The new time is "
         << hour << ":"
         << minute << ":"
         << second << " p.m.\n";

    return EXIT_SUCCESS;
}