50. Reverse an Array Using Only Pointers

#include <stdio.h>

void swap(int* a, int* b) {
    if(!(*a) || !(*b)) return;

    int temp = *a;
    *a = *b;
    *b = temp;
}

void reverse_array(int *ptr, int n) {
    if(!ptr || n <= 0) return;

    int* front = ptr;
    int* rear = ptr + n - 1;
    while(front < rear) swap(front++, rear--);
}

int main() {
    int n;
    scanf("%d", &n);

    int arr[100];
    for (int i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }

    reverse_array(arr, n);

    for (int i = 0; i < n; i++) {
        printf("%d", arr[i]);
        if(i < n-1){
            printf(" ");
        }
    }

    return 0;
}