• PQNode *pqueue_peek(PriorityQueue *pqueue);: Return a pointer to the head node of the specified queue (or NULL if the queue is empty). using int main(int argc, char *argv[]) without assert

#include <stdio.h>
#include <stdlib.h>
#include "priority_queue.h"

int main(int argc, char *argv[]){
    PriorityQueue *pqueue = pqueue_create();
    pqueue_push(pqueue, 'a', 1);
    pqueue_push(pqueue, 'b', 2);
    PQNode *pq = pqueue_peek(pqueue);
    if(pq == NULL){
        printf("no elements");
    }
    else{
        printf("%c", pq->data);
    }
    pqueue_destroy(pqueue);
    return 0;
}