import java.util.*;

class Process {
    int pid, at, bt, rt, ct, tat, wt; // rt = remaining time
    Process(int pid, int at, int bt) {
        this.pid = pid;
        this.at = at;
        this.bt = bt;
        this.rt = bt;
    }
}

public class RoundRobin {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        System.out.print("Enter number of processes: ");
        int n = sc.nextInt();

        Process[] processes = new Process[n];
        for (int i = 0; i < n; i++) {
            System.out.print("Enter Arrival Time and Burst Time for Process P" + (i + 1) + ": ");
            int at = sc.nextInt();
            int bt = sc.nextInt();
            processes[i] = new Process(i + 1, at, bt);
        }

        System.out.print("Enter Time Quantum: ");
        int tq = sc.nextInt();

        // Sort by arrival time
        Arrays.sort(processes, Comparator.comparingInt(p -> p.at));

        Queue<Process> queue = new LinkedList<>();
        int time = 0, completed = 0;
        boolean[] visited = new boolean[n];

        queue.add(processes[0]);
        visited[0] = true;
        time = processes[0].at;

        while (!queue.isEmpty()) {
            Process p = queue.poll();

            if (p.rt > tq) {
                p.rt -= tq;
                time += tq;
            } else {
                time += p.rt;
                p.rt = 0;
                p.ct = time;
                p.tat = p.ct - p.at;
                p.wt = p.tat - p.bt;
                completed++;
            }

            // Add processes that have arrived by current time
            for (int i = 0; i < n; i++) {
                if (!visited[i] && processes[i].at <= time) {
                    queue.add(processes[i]);
                    visited[i] = true;
                }
            }

            // If the current process still has remaining time, re-add it
            if (p.rt > 0) queue.add(p);

            // If queue is empty but some processes remain, jump to next arrival
            if (queue.isEmpty()) {
                for (int i = 0; i < n; i++) {
                    if (!visited[i]) {
                        queue.add(processes[i]);
                        visited[i] = true;
                        time = processes[i].at;
                        break;
                    }
                }
            }
        }

        // Print results
        System.out.println("\\nPID\\tAT\\tBT\\tCT\\tTAT\\tWT");
        int totalTAT = 0, totalWT = 0;
        for (Process p : processes) {
            System.out.println("P" + p.pid + "\\t" + p.at + "\\t" + p.bt + "\\t" +
                               p.ct + "\\t" + p.tat + "\\t" + p.wt);
            totalTAT += p.tat;
            totalWT += p.wt;
        }

        System.out.printf("\\nAverage TAT = %.2f\\n", (float) totalTAT / n);
        System.out.printf("Average WT  = %.2f\\n", (float) totalWT / n);

        sc.close();
    }
}