#include<stdio.h>

#define MAX 250

int left(int i);
int right(int i);
int parent(int i);

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

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

  for(i = 1;i <= H;i++){
    printf("node %d",i);
    printf(": key = %d",A[i]);
    putchar(',');
    putchar(' ');

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

  return 0;
}




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

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

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

