System Software Lab 8 | Read Now

System Software VTU Lab

Program 8:- Design, develop and implement a C/C++/Java program to implement Banker’s algorithm. Assume suitable input required to demonstrate the results.

System Software Lab 8 [lab8.c]

#include <stdio.h>
#include <stdlib.h>

int main()
{
 int Max[10][10], need[10][10], alloc[10][10], avail[10], completed[10], safeSequence[10];
 int p, r, i, j, process, count = 0;
 printf("Enter the no of processes : ");
 scanf("%d", &p);
 for(i = 0; i< p; i++)
  completed[i] = 0;
 
 printf("\n\nEnter the no of resources : ");
 scanf("%d", &r);
 printf("\n\nEnter the Max Matrix for each process : ");
 for(i = 0; i < p; i++)
 {
  printf("\nFor process %d : ", i + 1);
  for(j = 0; j < r; j++)
   scanf("%d", &Max[i][j]);
 }
 
 printf("\n\nEnter the allocation for each process : ");
 for(i = 0; i < p; i++)
 {
  printf("\nFor process %d : ",i + 1);
  for(j = 0; j < r; j++)
   scanf("%d", &alloc[i][j]);
 }
 
 printf("\n\nEnter the Available Resources : ");
 for(i = 0; i < r; i++)
  scanf("%d", &avail[i]);
 for(i = 0; i < p; i++)
  for(j = 0; j < r; j++)
   need[i][j] = Max[i][j] - alloc[i][j];

 do
 {
  printf("\n Max matrix:\tAllocation matrix:\n");
  for(i = 0; i < p; i++)
  {
   for( j = 0; j < r; j++)
    printf("%d ", Max[i][j]);
   printf("\t\t");
   for( j = 0; j < r; j++)
    printf("%d ", alloc[i][j]);
   printf("\n");
  }
  process = -1;
  for(i = 0; i < p; i++)
  {
   if(completed[i] == 0)//if not completed
   {
    process = i ;

    for(j = 0; j < r; j++)
    {
     if(avail[j] < need[i][j])
     {
      process = -1;
      break;
     }
    }
   }
   if(process != -1)
    break;
  }
  if(process != -1)
  {
   printf("\nProcess %d runs to completion!", process + 1);
   safeSequence[count] = process + 1;
   count++;
   for(j = 0; j < r; j++)
   {
    avail[j] += alloc[process][j];
    alloc[process][j] = 0;
    Max[process][j] = 0;
    completed[process] = 1;
   }
  }
 } while(count != p && process != -1);
 
 if(count == p)
 {
  printf("\nThe system is in a safe state!!\n"); printf("Safe Sequence : < "); for( i = 0; i < p; i++)
  printf("%d ", safeSequence[i]);
  printf(">\n");
 }
 else
  printf("\nThe system is in an unsafe state!!");
}

Output