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

#define SIZE 250

int main(){
  int i,n;
  int heap[SIZE];

  scanf("%d",&n);

  for(i = 1; i <= n; i++){
    scanf("%d",&heap[i]);
  }

  for(i = 1; i <= n; i++){
    printf("node %d: key = %d,",i ,heap[i]);
    if(i != 1){
      printf(" parent key = %d,",heap[i/2]);
    }
    if(2*i <= n){
      printf(" left key = %d,",heap[2*i]);
    }
    if(2*i+1 <= n){
      printf(" right key = %d,",heap[2*i+1]);
    }
    printf(" \n");
  }

  return 0;
}