++ and +=

Lab C++ Advanced 30 points

Write class Time (hours, minutes) with prefix ++ (adds one minute), += (adds minutes) and << printing HH:MM on a 24-hour clock. Read a start time and commands tick or add M; print the time after each.

Input

Line 1: HH MM. Line 2: n. Then n commands.

Output

n lines.

Example

Input

23 58
3
tick
tick
add 90

Output

23:59
00:00
01:30

Sample input available Sample output available

Editor

C++

Hints

Store the time as minutes since midnight and wrap with % 1440.

Prefix ++ returns *this by reference.

Solution explanation

Implementing ++ in terms of += avoids duplicating logic.

Show solution

#include <iostream>
#include <iomanip>
#include <string>
using namespace std;

class Time {
public:
    Time(int h, int m) : minutes_((h * 60 + m) % 1440) {}
    Time &operator++() { return *this += 1; }
    Time &operator+=(int m) {
        minutes_ = ((minutes_ + m) % 1440 + 1440) % 1440;
        return *this;
    }
    friend ostream &operator<<(ostream &out, const Time &t) {
        return out << setfill('0') << setw(2) << t.minutes_ / 60 << ":" << setw(2) << t.minutes_ % 60;
    }

private:
    int minutes_;
};

int main() {
    int h, m, n;
    cin >> h >> m >> n;
    Time t(h, m);
    for (int i = 0; i < n; i++) {
        string cmd;
        cin >> cmd;
        if (cmd == "tick") {
            ++t;
        } else {
            int mins;
            cin >> mins;
            t += mins;
        }
        cout << t << "\n";
    }
    return 0;
}

Output

Answer