#include <stdio.h>

// ── PAGING ────────────────────────────────────────────────────────────────
void paging() {
    int page_size, num_pages;
    printf("\n--- PAGING ---\n");
    printf("Enter page size: ");
    scanf("%d", &page_size);
    printf("Enter number of pages: ");
    scanf("%d", &num_pages);

    int page_table[num_pages];
    printf("Enter frame number for each page:\n");
    for (int i = 0; i < num_pages; i++) {
        printf("  Page %d -> Frame: ", i);
        scanf("%d", &page_table[i]);
    }

    int logical;
    printf("Enter logical address: ");
    scanf("%d", &logical);

    int page  = logical / page_size;   // which page
    int offset = logical % page_size;  // offset within page

    if (page >= num_pages) {
        printf("Invalid! Page %d does not exist.\n", page);
        return;
    }

    int frame   = page_table[page];
    int physical = frame * page_size + offset;

    printf("\nPage Number : %d\n", page);
    printf("Offset      : %d\n", offset);
    printf("Frame Number: %d\n", frame);
    printf("Physical Address: %d\n", physical);
}

// ── SEGMENTATION ──────────────────────────────────────────────────────────
void segmentation() {
    int num_seg;
    printf("\n--- SEGMENTATION ---\n");
    printf("Enter number of segments: ");
    scanf("%d", &num_seg);

    int base[num_seg], limit[num_seg];
    printf("Enter base and limit for each segment:\n");
    for (int i = 0; i < num_seg; i++) {
        printf("  Segment %d -> Base: ", i);
        scanf("%d", &base[i]);
        printf("  Segment %d -> Limit: ", i);
        scanf("%d", &limit[i]);
    }

    int seg, offset;
    printf("Enter segment number: ");
    scanf("%d", &seg);
    printf("Enter offset: ");
    scanf("%d", &offset);

    if (seg >= num_seg) {
        printf("Invalid! Segment %d does not exist.\n", seg);
        return;
    }

    if (offset >= limit[seg]) {
        printf("Segmentation Fault! Offset %d exceeds limit %d.\n", offset, limit[seg]);
        return;
    }

    int physical = base[seg] + offset;
    printf("\nSegment Base  : %d\n", base[seg]);
    printf("Segment Limit : %d\n", limit[seg]);
    printf("Offset        : %d\n", offset);
    printf("Physical Address: %d\n", physical);
}

// ── MAIN ──────────────────────────────────────────────────────────────────
int main() {
    int ch;
    while (1) {
        printf("\n1. Paging");
        printf("\n2. Segmentation");
        printf("\n3. Exit");
        printf("\nEnter choice: ");
        scanf("%d", &ch);

        if      (ch == 1) paging();
        else if (ch == 2) segmentation();
        else if (ch == 3) break;
        else printf("Invalid choice\n");
    }
    return 0;
}