#include<stdio.h>
#define H 255

int main(){
  int heap[H];
  int n,i;

  scanf("%d",&n);
  for(i=1;i<=n;i++) scanf("%d",&heap[i]);

  for(i=1;i<=n;i++){
    printf("node %d: ",i);
    printf("key = %d, ",heap[i]);
    if(i/2 != 0)   printf("parent key = %d, ",heap[i/2]);
    if(2*i <= n)   printf("left key = %d, ",heap[2*i]);
    if(2*i+1 <= n) printf("right key = %d, ",heap[2*i+1]);
    printf("\n");
  }

  return 0;
}

