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Deadlock Prevention using Banker’s Algorithm in C Programming

#include< stdio.h>
#include< conio.h>
void main()
{
 int allocated[15][15],max[15][15],need[15][15],avail[15],tres[15],work[15],flag[15];
 int pno,rno,i,j,prc,count,t,total;
 count=0;
 clrscr();

 printf("\n Enter number of process:");
 scanf("%d",&pno);
 printf("\n Enter number of resources:");
 scanf("%d",&rno);
 for(i=1;i< =pno;i++)
 {
  flag[i]=0;
 }
 printf("\n Enter total numbers of each resources:");
 for(i=1;i<= rno;i++)
  scanf("%d",&tres[i]);


 printf("\n Enter Max resources for each process:");
 for(i=1;i<= pno;i++)
 {
  printf("\n for process %d:",i);
  for(j=1;j<= rno;j++)
   scanf("%d",&max[i][j]);
 }


 printf("\n Enter allocated resources for each process:");
 for(i=1;i<= pno;i++)
 {
  printf("\n for process %d:",i);
  for(j=1;j<= rno;j++)
   scanf("%d",&allocated[i][j]);


 }

 printf("\n available resources:\n");
 for(j=1;j<= rno;j++)
 {
  avail[j]=0;
  total=0;
  for(i=1;i<= pno;i++)
  {
   total+=allocated[i][j];
  }
  avail[j]=tres[j]-total;
  work[j]=avail[j];
  printf("     %d \t",work[j]);
 }


 do
 {



 for(i=1;i<= pno;i++)
 {
  for(j=1;j<= rno;j++)
  {
   need[i][j]=max[i][j]-allocated[i][j];
  }
 }

 printf("\n Allocated matrix        Max      need");
 for(i=1;i<= pno;i++)
 {
  printf("\n");
  for(j=1;j<= rno;j++)
  {
   printf("%4d",allocated[i][j]);
  }
  printf("|");
  for(j=1;j<= rno;j++)
  {
   printf("%4d",max[i][j]);
  }
   printf("|");
  for(j=1;j<= rno;j++)
  {
   printf("%4d",need[i][j]);
  }
 }




  prc=0;

  for(i=1;i<= pno;i++)
  {
   if(flag[i]==0)
   {
    prc=i;

    for(j=1;j<= rno;j++)
    {
     if(work[j]< need[i][j])
     {
       prc=0;
       break;
     }
    }
   }

   if(prc!=0)
   break;
  }

  if(prc!=0)
  {
   printf("\n Process %d completed",i);
   count++;
   printf("\n Available matrix:");
   for(j=1;j<= rno;j++)
   {
    work[j]+=allocated[prc][j];
    allocated[prc][j]=0;
    max[prc][j]=0;
    flag[prc]=1;
    printf("   %d",work[j]);
   }
  }

 }while(count!=pno&&prc!=0);

 if(count==pno)
  printf("\nThe system is in a safe state!!");
 else
  printf("\nThe system is in an unsafe state!!");
 
getch();
}

OUTPUT


Enter number of process:5

 Enter number of resources:3

 Enter total numbers of each resources:10 5 7

 Enter Max resources for each process:
 for process 1:7 5 3

 for process 2:3 2 2

 for process 3:9 0 2

 for process 4:2 2 2

 for process 5:4 3 3

 Enter allocated resources for each process:
 for process 1:0 1 0

 for process 2:3 0 2


 for process 3:3 0 2

 for process 4:2 1 1

 for process 5:0 0 2

 available resources:
     2       3       0


 Allocated matrix        Max      need
   0   1   0|   7   5   3|   7   4   3
   3   0   2|   3   2   2|   0   2   0
   3   0   2|   9   0   2|   6   0   0
   2   1   1|   2   2   2|   0   1   1
   0   0   2|   4   3   3|   4   3   1
 Process 2 completed
 Available matrix:   5   3   2
 Allocated matrix        Max      need
   0   1   0|   7   5   3|   7   4   3
   0   0   0|   0   0   0|   0   0   0
   3   0   2|   9   0   2|   6   0   0
   2   1   1|   2   2   2|   0   1   1
   0   0   2|   4   3   3|   4   3   1
 Process 4 completed
 Available matrix:   7   4   3
 Allocated matrix        Max      need
   0   1   0|   7   5   3|   7   4   3
   0   0   0|   0   0   0|   0   0   0
   3   0   2|   9   0   2|   6   0   0
   0   0   0|   0   0   0|   0   0   0
   0   0   2|   4   3   3|   4   3   1
 Process 1 completed
 Available matrix:   7   5   3
 Allocated matrix        Max      need
   0   0   0|   0   0   0|   0   0   0
   0   0   0|   0   0   0|   0   0   0
   3   0   2|   9   0   2|   6   0   0
   0   0   0|   0   0   0|   0   0   0
   0   0   2|   4   3   3|   4   3   1
 Process 3 completed
 Available matrix:   10   5   5
 Allocated matrix        Max      need
   0   0   0|   0   0   0|   0   0   0
   0   0   0|   0   0   0|   0   0   0
   0   0   0|   0   0   0|   0   0   0
   0   0   0|   0   0   0|   0   0   0
   0   0   2|   4   3   3|   4   3   1
 Process 5 completed
 Available matrix:   10   5   7
The system is in a safe state!!

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