lfu.c

#include<stdio.h>

int main()
{
	int total_frames, total_pages, hit = 0;
	int pages[25], frame[10], arr[25], time[25];
	int m, n, page, flag, k, minimum_time, temp;
	printf("Enter Total Number of Pages:\t");
	scanf("%d", &total_pages);
	printf("Enter Total Number of Frames:\t");
	scanf("%d", &total_frames);
	for(m = 0; m < total_frames; m++)
	{
		frame[m] = -1;
	}
	for(m = 0; m < 25; m++)
	{
		arr[m] = 0;
	}
	printf("Enter Values of Reference String\n");
	for(m = 0; m < total_pages; m++)
	{
		printf("Enter Value No.[%d]:\t", m + 1);
		scanf("%d", &pages[m]);
	}
  	printf("\n");
  	for(m = 0; m < total_pages; m++)
  	{
    		arr[pages[m]]++;
    		time[pages[m]] = m;
    		flag = 1;
    		k = frame[0];
    		for(n = 0; n < total_frames; n++)
    		{
      			if(frame[n] == -1 || frame[n] == pages[m])
      			{
        			if(frame[n] != -1)
        			{
            				hit++;
        			}
        			flag = 0;
        			frame[n] = pages[m];
        			break;
      			}
      			if(arr[k] > arr[frame[n]])
      			{
        			k = frame[n];
      			}
    		}
    		if(flag)
    		{
      			minimum_time = 25;
      			for(n = 0; n < total_frames; n++)
      			{
        			if(arr[frame[n]] == arr[k] && time[frame[n]] < minimum_time)
        			{
          				temp = n;
          				minimum_time = time[frame[n]];
        			}
      			}
      			arr[frame[temp]] = 0;
      			frame[temp] = pages[m];
    		}
    		for(n = 0; n < total_frames; n++)
		{
      			printf("%d\t", frame[n]);
    		}
    		printf("\n");
  	}
  	printf("Page Hit:\t%d\n", hit);
  	return 0;
}