#include <stdio.h>
#define MAX 251
 
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 i,n,heap[MAX];

  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[parent(i)]);
    }

    int l=left(i);
    int r=right(i);

    if(l <= n){
    printf("left key = %d, ",heap[l]);
    }
    if(r <= n){
    printf("right key = %d, ",heap[r]);
    }
    printf("\n");
  }
  return 0;
}