OS-practical/slip18_1.c at main · mukmal/OS-practical · GitHub

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#include<stdio.h>
int frame[5][2],nf;
int searchFrames(int sv)
{
    int x;
    for(x=0;x<nf;x++)
    {
        if(sv==frame[x][0])
        {
            return x;
        }
    }
    return -2;
}
void displayMemory()
{
    int i;
    printf("\n\nFrame Contains |");
    for(i=0;i<nf;i++)
        printf(" %d  | ",frame[i][0]);
}
int findFreeFrame()
{
    int i,min=frame[0][1],ri=0;
    for(i=0;i<nf;i++)
    {
        if(frame[i][1]==-1)
        {
            return i;
        }
    }
    for(i=0;i<nf;i++)
    {
           if(min>frame[i][1])
        {
        }
    }
            min=frame[i][1];
            ri=i;
    return ri;
}
 int main()
{
    int rs[]={3,5,7,2,5,1,2,3,1,3,5,3,1,6,2};
    int ts=0;
    int n=15,i,j,pf=0,srch,insert_index;
    printf("Enter how many frames");
    scanf("%d",&nf);
    for(i=0;i<nf;i++)
    {
        for(j=0;j<2;j++)
            frame[i][j]=-1;
    }
    displayMemory();
    for(i=0;i<n;i++)
    {
        srch=searchFrames(rs[i]);
        if(srch==-2)
        {
            pf++;
            insert_index=findFreeFrame();
            frame[insert_index][0]=rs[i];
            frame[insert_index][1]=ts++;
        }
        else
        {
            frame[srch][1]=ts++;
        }
        displayMemory();
    }
    printf("\n\nTotal Page Faults Occured is %d\n",pf);
}