LRU Page Replacement Algorithm

// Least Recently Used (LRU) Page Replacement Algorithm
#include <stdio.h>
#include <stdbool.h>

// Function which runs the algorithm and in the end, returns no. of page faults

int LRU_algorithm(int totalPages, int pages[], int totalFrames, int frames[])
{
    int i, j, k;
    int pageFaults = 0;

    for (i = 0; i < totalPages; i++)
    {
        int currentPage = pages[i];

        // Check if Page Already Exists
        bool found = false;
        for (j = 0; j < totalFrames; j++)
        {
            if (frames[j] == currentPage)
            {
                found = true;
                break;
            }
        }
        // If Page Already Exists, Page Hit
        if (found == true)
        {
            for (j = 0; j < totalFrames; j++)
            {
                printf("%d \t", frames[j]);
            }
            printf("Page Hit !\n");
        }
        // If Not, Already Frame lo unnavati lo max distance to the left of current page em ochindo adhi replace aitadi
        else
        {
            int maxDistance = -1;
            int indexToBeReplaced;

            // calculate that distance for every frame
            for(j = 0; j < totalFrames; j++)
            {
                int distance = 0;
                for(k = i - 1; k >= 0; k--)
                {
                    if(frames[j] != pages[k])
                    {
                        distance++;
                    }
                    else
                    {
                        break;
                    }
                }
                if(distance > maxDistance)
                {
                    maxDistance = distance;
                    indexToBeReplaced = j;
                }
            }

            frames[indexToBeReplaced] = pages[i];

            // Increment Page Faults
            pageFaults++;
            for (j = 0; j < totalFrames; j++)
            {
                printf("%d \t", frames[j]);
            }
            printf("Page Fault !\n");
        }
    }
    return pageFaults;
}

int main()
{
    int totalPages = 19;
    int pages[] = {3, 2, 1, 3, 4, 1, 6, 2, 4, 3, 4, 2, 1, 4, 5, 2, 1, 3, 4};

    int totalFrames = 3;
    int frames[totalFrames];

    int i;
    for (i = 0; i < totalFrames; i++)
    {
        frames[i] = -1;
    }

    printf("Total Number of Page Faults = %d\n", LRU_algorithm(totalPages, pages, totalFrames, frames));
}