Enqueue and dequeue in queue

 #include <stdio.h>

#include <stdlib.h>

#define MAX 100

int queue[MAX];

int front = -1, rear = -1;

void enqueue(int value) {

    if (rear == MAX - 1) {

        printf("Queue Overflow\n");

        return;

    }

    if (front == -1) {

        front = 0;

    }

    queue[++rear] = value;

}

int dequeue() {

    if (front == -1 || front > rear) {

        printf("Queue Underflow\n");

        return -1;

    }

    return queue[front++];

}

int main() {

    enqueue(10);

    enqueue(20);

    enqueue(30);

    printf("%d dequeued from queue\n", dequeue());

    printf("%d dequeued from queue\n", dequeue());

    printf("%d dequeued from queue\n", dequeue());

    return 0;

}