CPU Scheduling Algorithm - Round Robin(Java)

This is a Java program which implements one of the CPU Scheduling algorithm called Round Robin(RR). Round robin algorithm is mainly used in time sharing systems , it is also similar to First Come First Served(FCFS) algorithm but FCFS does not have that time slicing switch. All the jobs gets executed in this scheduling algorithm , so the advantage here is , its Starvation free.

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PROGRAM :

package mycodingcorner;

import java.util.Scanner;

public class RoundRobin {
 public static void main(String[] args) {
  int i, j, n, r, q, e = 0;
  int bt_c[] = new int[10];
  int bt[] = new int[10];
  int m[] = new int[50];
  float f, avg = 0;
  Scanner scan = new Scanner(System.in);
  System.out.print("\nEnter how many jobs ?\t");
  n = scan.nextInt();
  for (i = 1; i <= n; i++) {
   System.out.print("Enter burst time for job " + i + " :\t");
   bt[i] = scan.nextInt();
   bt_c[i] = bt[i]; // stores job has how much burst time in array i
  }
  System.out.print("\nEnter Quantum (time slice value) :\t");
  q = scan.nextInt();
  int max = 0;
  max = bt[1];
  for (j = 1; j <= n; j++)
   if (max <= bt[j])
    max = bt[j];

  if ((max % q) == 0)
   r = (max / q);
  else
   r = (max / q) + 1;
  for (i = 1; i <= r; i++) {
   System.out.print("\n\nRound" + i);
   for (j = 1; j <= n; j++) {
    if (bt[j] > 0) {
     bt[j] = bt[j] - q;

     if (bt[j] <= 0) {
      bt[j] = 0;
      System.out.print("\njob " + j + " is completed");
     } else
      System.out.print("\njob" + j + " remaining time is " + bt[j]);
    }
   }

  }
  for (i = 1; i <= n; i++) {
   e = 0;
   for (j = 1; j <= r; j++) {
    if (bt_c[i] != 0) {
     if (bt_c[i] >= q) {
      m[i + e] = q;
      bt_c[i] -= q;
     } else {
      m[i + e] = bt_c[i];
      bt_c[i] = 0;
     }
    } else
     m[i + e] = 0;
    e = e + n;
   }
  }
  for (i = 2; i <= n; i++)
   for (j = 1; j <= i - 1; j++)
    avg = avg + m[j];
  for (i = n + 1; i <= r * n; i++) {
   if (m[i] != 0) {
    for (j = i - (n - 1); j <= i - 1; j++)
     avg = m[j] + avg;
   }
  }
  f = avg / n;
  System.out.print("\n\n\nTOTAL WATING TIME: \t" + avg);
  System.out.print("\n\nAVERAGE WAITING TIME: \t\n" + f);
  scan.close();
 }
}

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OUTPUT :

Java - Cpu Scheduling Algorithm - Round Robin(RR)