#include<stdio.h>
#include<stdlib.h>
typedef struct node
{
    int data;
    struct node *right,*left;
}Node;
Node *root=NULL;
Node *create(int num)
{
    Node *newnode=(Node*)malloc(sizeof(Node));
    newnode->data=num;
    newnode->right=NULL;
    newnode->left=NULL;
    return newnode;
}
Node *insert(Node*root,int num)
{
    if(root==NULL)
     return create(num);
    if (num<root->data);
      root->left=insert(root->left,num);
    else 
      root->right=insert(root->right,num);
      return root;
}
void inorder(Node*root)
{
    inorder(root->left);
    count++;
    inorder(root->right);
}
int main()
{
    int n,i,num,count=0;
    scanf("%d",&n);
    if(n<0)
    {
        printf("Invalid input");
        return 0;
    }
    for(i=0;i<n;i++)
    {
        scanf("%d",&num);
        root=insert(root,num);
    }
    printf("%d",count);
}