50. Reverse an Array Using Only Pointers

#include <stdio.h>

void reverse_array(int *ptr, int n) {
    int *ptr_end= ptr+n-1;
    while(ptr<ptr_end){
        *ptr ^= *ptr_end;
        *ptr_end ^= *ptr;
        *ptr ^= *ptr_end;
        ptr++;
        ptr_end--;
    }
    return;
}

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;
}