#include <stdio.h>
#include <stdlib.h>
#define MAX_FRAMES 10 // Maximum number of frames, adjust as needed
#define REFERENCE_STRING_LENGTH 15 // Length of the reference string
void mru_page_replacement(int reference_string[], int n_frames, int length) {
int memory[MAX_FRAMES];
int page_faults = 0;
int page_order[MAX_FRAMES];
int page_index = 0;
int memory_count = 0;
int mru_index = -1;
// Initialize memory and page_order
for (int i = 0; i < n_frames; i++) {
memory[i] = -1;
}
printf("Reference String: ");
for (int i = 0; i < length; i++) {
printf("%d ", reference_string[i]);
}
printf("\n");
printf("Frame Status:\n");
for (int i = 0; i < length; i++) {
int page = reference_string[i];
int found = 0;
// Check if the page is already in memory
for (int j = 0; j < n_frames; j++) {
if (memory[j] == page) {
found = 1;
// Update MRU index for the most recently used page
mru_index = j;
break;
}
}
if (!found) {
// Page fault occurs
if (memory_count < n_frames) {
// Memory is not full
memory[memory_count] = page;
mru_index = memory_count;
memory_count++;
} else {
// Memory is full, replace the MRU page
memory[mru_index] = page;
// Find new MRU index
for (int j = 0; j < n_frames; j++) {
if (page_order[j] == page) {
mru_index = j;
break;
}
}
}
page_faults++;
}
// Update page_order
if (mru_index != -1) {
page_order[memory_count - 1] = page;
}
// Print current memory state
printf("After reference %d:\n", page);
for (int j = 0; j < n_frames; j++) {
if (memory[j] != -1) {
printf("%d ", memory[j]);
} else {
printf("- ");
}
}
printf("\n");
}
printf("Total page faults: %d\n", page_faults);
}
int main() {
int reference_string[REFERENCE_STRING_LENGTH] = {3, 5, 7, 2, 5, 1, 2, 3, 1, 3, 5, 3, 1, 6, 2};
int n_frames = 3; // Number of frames in memory
mru_page_replacement(reference_string, n_frames, REFERENCE_STRING_LENGTH);
return 0;
}
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