stopwatch

#include <iostream>
#include <ctime>
//<ctime> headerfile/set of functions, macros and types to work with date and time.
#include <chrono>
//chrono is a headerfile ./and type of function to work with time

using namespace std;
using namespace std::chrono;
// std::chrono::duration represents a time interval


int main() 
{
    bool is_running = false;
    time_t start_time, end_time;
    double elapsed_time = 0;
    //elapsed time:two timestamps/ at the beginning of the code and the other at the end.


    while (true) {
        cout << "Press s to start, p to stop, r to reset, or q to quit: ";
        char input;
        cin >> input;

        if (input == 's') {
            if (!is_running) {
                start_time = time(nullptr);
                is_running = true;
                cout << "Stopwatch started." << endl;
            }
            else {
                cout << "Stopwatch is already running." << endl;
            }
        }
        else if (input == 'p') {
            if (is_running) {
                end_time = time(nullptr);
                elapsed_time += difftime(end_time, start_time);
                is_running = false;
                cout << "Elapsed time: " << elapsed_time << " seconds." << endl;
            }
            else {
                cout << "Stopwatch is not running." << endl;
            }
        }
        else if (input == 'r') {
            is_running = false;
            elapsed_time = 0;
            cout << "Stopwatch reset." << endl;
        }
        else if (input == 'q') {
            cout << "Goodbye!" << endl;
            break;
        }
        else {
            cout << "Invalid input." << endl;
        }
    }

    return 0;
}