#include <stdio.h>

int heap[250];

int main()
{
  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: key = %d, ",i,heap[i]);
    if(i!=1) 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;
}

