50. Reverse an Array Using Only Pointers

#include <stdio.h>

void reverse_array(int *ptr, int n) {
    // Your logic here
    int *left = ptr, *right = ptr + n-1;

    while(left < right){
        int temp =*left;
        *left = *right;
        *right = temp;
        left++;
        right--;
    }
}

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;
}

Use left and right pointers pointing to the first and last element of the array, and keep swapping till you converge in the center.