Example: Calculate the Difference Between Two Time Periods in C++ using time.h

// DIFFERENCE BETWEEN TWO TIME PERIODS in C++ using time.h
#include <iostream>
#include <ctime>
using namespace std;

int main()
{
    // Step-1 Declare two time structures
    struct tm time1 = {0}, time2 = {0};

    // Step-2 Initialize the first time (YYYY-MM-DD HH:MM:SS)
    time1.tm_year = 2025 - 1900; // Year since 1900
    time1.tm_mon = 4;            // May (0-based index)
    time1.tm_mday = 1;
    time1.tm_hour = 10;
    time1.tm_min = 30;
    time1.tm_sec = 0;

    // Step-3 Initialize the second time
    time2.tm_year = 2025 - 1900;
    time2.tm_mon = 4;
    time2.tm_mday = 9;
    time2.tm_hour = 15;
    time2.tm_min = 45;
    time2.tm_sec = 0;

    // Step-4 Convert both structures to time_t (epoch time)
    time_t t1 = mktime(&time1);
    time_t t2 = mktime(&time2);

    // Step-5 Find the difference in seconds
    double seconds = difftime(t2, t1);

    // Step-6 Convert seconds to hours, minutes, seconds
    int hours = seconds / 3600;
    int minutes = ((int)seconds % 3600) / 60;
    int remainingSeconds = (int)seconds % 60;

    // Step-7 Display the result
    cout << "\nTIME DIFFERENCE: " << hours << " HOURS, "
         << minutes << " MINUTES, "
         << remainingSeconds << " SECONDS\n";

    return 0;
}