#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",i);
    printf(": key = %d, ",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;
}

