#include<stdio.h>
#define N  500

int main (void){
  int A[N],num,i=0;
  
  scanf("%d",&num);
  for (i=1;i<=num;i++){
    scanf("%d",&A[i]);
  }
  for(i=1;i<=num;i++){
    printf("node %d: key = %d, ",i,A[i]);
    if(i!=1)printf("parent key = %d, ",A[i/2]);
    else  if(i*2<=num)printf("left key = %d, ",A[i*2]);
    else if(i*2+1<=num)printf("right key = %d, ",A[i*2+1]);
    printf("\n");
  }
    return 0;
}
    