Reverse an Array Using Only Pointers

Code

#include <stdio.h>

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

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

int main(void) {
    int n;
    
    if (scanf("%d", &n) != 1 || n < 1 || n > 100) {
        fprintf(stderr, "Invalid size (1–100 expected)\n");
        return 1;
    }

    int arr[100];
    for (int i = 0; i < n; i++) {
        if (scanf("%d", &arr[i]) != 1) {
            fprintf(stderr, "Error reading element %d\n", i);
            return 1;
        }
    }

    reverse_array(arr, n);

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

    return 0;
}

Solving Approach