/* program to implement page replacement using FIFO algorithm*/#include<stdio.h>int re[30],p[10],i,j,n,nr,line=6,c=0,a1=0;main(){

clrscr();printf(" enter length of reference string:");scanf("%d",&nr);printf(" enter reference string:");for(i=1;i<=nr;i++){

scanf("%d",&re[i]);}printf(" \n enter number of frames:");fflush(stdin);scanf("%d",&n);for(i=1;i<=n;i++)p[i]=-1;for(i=1,j=1;i<=nr;i++){

a1=0;if(j>n)j=1;for(c=1;c<=n;c++)if(re[i]==p[c])a1++;if(a1==0){

p[j]=re[i];j++;

}display(n,p,i);

}printf("\n");getch();

}

display(int no,int p[],int i){

int k;if(i==1){

printf("\t\t\t");for(k=1;k<=no;k++)printf("_ _");

}printf("\n%8d",re[i]);gotoxy(25,line++);for(k=1;k<=no;k++){

printf("|");printf("_");if(p[k]!=-1)

1

printf("%d",p[k]);elseprintf(" ");printf("_");

}printf("|");

}

2