Solution.c

#include <stdio.h>
#define SIZE 100

int queue[SIZE], front = -1, rear = -1;

void enqueue(int value) {
    if (rear == SIZE - 1) {
        printf("Queue is full!\n");
    } else {
        if (front == -1) front = 0;
        queue[++rear] = value;
        printf("Inserted: %d\n", value);
    }
}

void dequeue() {
    if (front == -1 || front > rear) {
        printf("Queue is empty!\n");
    } else {
        printf("Removed: %d\n", queue[front++]);
        if (front > rear) front = rear = -1;
    }
}

void display() {
    if (front == -1) {
        printf("Queue is empty!\n");
    } else {
        printf("Queue elements: ");
        for (int i = front; i <= rear; i++) {
            printf("%d ", queue[i]);
        }
        printf("\n");
    }
}

int main() {
    int choice, value;

    while (1) {
        printf("\n1. Enqueue\n2. Dequeue\n3. Display\n4. Exit\n");
        printf("Enter your choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                printf("Enter value to insert: ");
                scanf("%d", &value);
                enqueue(value);
                break;
            case 2:
                dequeue();
                break;
            case 3:
                display();
                break;
            case 4:
                return 0;
            default:
                printf("Invalid choice!\n");
        }
    }
}