#include <stdlib.h>
#include <stdio.h>

int is_heap(int* arr, int size ){
    for(int i = 0; i < size; i++){
        int l = i * 2 + 1;
        int r = i * 2 + 2;
    }
    
    if (left < size && arr[i] < arr[left]){
        return 0;
    }
    
    if (right < size && arr[i] < arr[right]){
        return 0;
    }
    return 1;
}

int main() {
    int arr[] = 100; 
    int size = 0;
    
    while (scanf("%d", &num) != EOF){
        arr[size++] = num;
    }
    
    if (!is_heap(arr, size)){
        printf("Nie je kopa.");
    }
    
    return 0;
}