cooked 3

9.c

@@ -0,0 +1,63 @@
+#include <stdio.h>
+
+#define MAX 50
+
+int stack[MAX], top = -1;
+
+// check if page is in stack
+int inStack(int page, int frames) {
+    for (int i = top; i > top - frames && i >= 0; i--)
+        if (stack[i] == page) return i;
+    return -1;
+}
+
+int main() {
+    int pages[MAX], n, frames;
+
+    printf("Enter number of pages: ");
+    scanf("%d", &n);
+    printf("Enter reference string: ");
+    for (int i = 0; i < n; i++)
+        scanf("%d", &pages[i]);
+    printf("Enter number of frames: ");
+    scanf("%d", &frames);
+
+    int faults = 0;
+
+    printf("\nPage\tFrames\t\t\tFault\n");
+
+    for (int i = 0; i < n; i++) {
+        int pos = inStack(pages[i], frames);
+
+        printf("%d\t", pages[i]);
+
+        if (pos == -1) {
+            // page not found — fault
+            stack[++top] = pages[i];
+            faults++;
+
+            // print current frames (top 'frames' elements)
+            int start = top - frames + 1;
+            if (start < 0) start = 0;
+            for (int j = start; j <= top; j++)
+                printf("%d ", stack[j]);
+            printf("\t\tFault");
+        } else {
+            // page found — move it to top (most recently used)
+            for (int j = pos; j < top; j++)
+                stack[j] = stack[j + 1];
+            stack[top] = pages[i];
+
+            // print current frames
+            int start = top - frames + 1;
+            if (start < 0) start = 0;
+            for (int j = start; j <= top; j++)
+                printf("%d ", stack[j]);
+        }
+
+        printf("\n");
+    }
+
+    printf("\nTotal Page Faults: %d\n", faults);
+    return 0;
+}