#include <stdio.h>
int parent(int);
int left(int);
int right(int);

int main(){
  int i,H,A[251];

  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("rightt key = %d, ",A[right(i)]);
    printf("\n");
  }

  return 0;
}

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

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

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