SJF

#include <stdio.h>
int main() 
{
      int AT[10], BT[10], var[10];
      int k, MIN, counter = 0, tim, totalp;
      double WT = 0, TAT = 0, CT;
      float AVG_WT, AVG_TAT;
      printf("\n\t\t\t**********SHORTEST JOB FIRST ALGORITHM (PREEMPTIVE)**********");
      printf("\n\n\n\nEnter Total Number of Processes to be taken:\t");
      scanf("%d", &totalp); 
      printf("\nEnter Burst Time for all processes ::\n" );
      for(k = 0; k < totalp; k++)
      {   
	        printf(" P%d  -\t",k+1);
            scanf("%d", &BT[k]); 
            var[k] = BT[k];
      }
      printf("\nEnter Arrival Time for all processes ::\n");
      for(k = 0; k < totalp; k++)
      {
      	 printf(" P%d  -\t",k+1);
		 scanf("%d", &AT[k]);
	  }
      BT[20] = 10000;  
      for(tim = 0; counter != totalp; tim++)
      {
            MIN = 20;
            for(k = 0; k < totalp; k++)
            {
                  if(AT[k] <= tim && BT[k] < BT[MIN] && BT[k] > 0)
                  {
                        MIN = k;
                  }
            }
            BT[MIN]--;
            if(BT[MIN] == 0)
            {
                  counter++;
                  CT = tim + 1;
                  WT = WT + CT - AT[MIN] - var[MIN];
                  TAT = TAT + CT - AT[MIN];
            }  
      }
      AVG_WT = WT / totalp; 
      AVG_TAT = TAT / totalp;
      printf("\nThe results are::");
      printf("\nAverage WaitingTime(AVG_WT):\t%f\n", AVG_WT);
      printf("Average TurnAroundTime(AVG_TAT):\t\t%f\n", AVG_TAT);
      return 0;
}