#include <stdio.h>
#include <stdbool.h>

bool is_min_heap(int arr[], int n) {
    for (int i = 0; i < n; i++) {
        int l = 2 * i + 1;
        int r = 2 * i + 2;
        if ((l < n && arr[i] > arr[l]) || (r < n && arr[i] > arr[r])) {
            return false;
        }
    }
    return true;
}

void preorder(int arr[], int n, int index, int level) {
    if (index >= n) return;
    for (int i = 0; i < level; i++) {
        printf(" ");
    }
    printf("%d\n", arr[index]);
    preorder(arr, n, 2 * index + 1, level + 1);
    preorder(arr, n, 2 * index + 2, level + 1);
}

int main() {
    int arr[100];
    int n = 0;
    while (scanf("%d", &arr[n]) != EOF) {
        n++;
    }
    if (is_min_heap(arr, n)) {
        printf("Je to taka kopa:\n");
        preorder(arr, n, 0, 0);
    } else {
        printf("Nie je kopa.\n");
    }
    return 0;
}