#include<stdio.h>
#define N 250

int parent(int i){
  return i/2;
}

int left(int i){
  return 2*i;
}

int right(int i){
  return 2*i+1;
}

int main(void){
  int heap_size, i, A[N];
  
  scanf("%d", &heap_size);
  for(i=1; i<=heap_size; i++) scanf("%d", &A[i]);
  
  for(i=1; i<=heap_size; i++){
    
    printf("node %d; key = %d, ", i, A[i]);
    
    if(parent(i) > 0) printf("parent key = %d, ", A[parent(i)]);
    if(left(i) <= heap_size) printf("left key = %d, ", A[left(i)]);
    if(right(i) <= heap_size) printf("right key = %d, ", A[right(i)]);
    
    printf("\n");
    
  }
  return 0;
}