#include <stdio.h>

int main() {
    int n, oldVal, newVal, found = 0;

    // Read n
    if (scanf("%d", &n) != 1 || n < 0 || n > 1000) {
        printf("Invalid input\n");
        return 0;
    }

    int arr[n];

    // Read array
    for (int i = 0; i < n; i++) {
        if (scanf("%d", &arr[i]) != 1) {
            printf("Invalid input\n");
            return 0