#include <stdio.h>
#include <stdlib.h>

typedef struct node* link;

struct node
{
int key;
link l,r;
};

link load(int count)
{ // Linear-time inorder loading of BST from file
int leftCount,rightCount;
link work,left;

if (count==0)
  return NULL;

leftCount=count/2;
rightCount=count-leftCount-1;

left=load(leftCount);
work=(link) malloc(sizeof(struct node));
work->l=left;
scanf("%d",&work->key);
work->r=load(rightCount);
return work;
}

void check(link root, int *lastKey)
{
if (!root)
  return;
check(root->l,lastKey);
if (*lastKey >= root->key)
{
  printf("Inorder error %d %d\n",*lastKey,root->key);
  exit(0);
}
*lastKey=root->key;
check(root->r,lastKey);
}

void print(link h,int level)
{ // Print indented tree from right-to-left
int i;

if (!h)
{
  for (i=0;i<level;i++)
    printf("   ");
  printf(".\n");
  return;
}

print(h->r,level+1);
for (i=0;i<level;i++)
  printf("   ");
printf("%d\n",h->key);
print(h->l,level+1);
}

int main()
{
int n;
link root;
int lastKey=(-999999);

scanf("%d",&n);

root=load(n);

check(root,&lastKey);

print(root,0);
}