#include<stdio.h>
#define MAX 100000

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

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

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

int main(){
  int H, i, A[MAX+1];

  scanf("%d",&H);

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

  for(i=1; i<=H; i++){
    printf("node %d; key = %d,",i ,A[i]);
    if(parent(i) >= 1){
      printf("parent key = %d,",A[parent(i)]);
    }
    if(left(i) <= H){
      printf("left key = %d,",A[left(i)]);
    }
    if(right(i) <= H){
      printf("right key = %d,",A[right(i)]);
    }

    printf("\n");
  }

  return 0;
}