#include<stdio.h>
#include<stdlib.h>
#include<stdbool.h>
typedef struct node
{
    int data;
    struct node *left, *right;
}Node;
Node *root=NULL;
Node* create(int num)
{
    Node *newNode = (Node*) malloc (1 * sizeof(Node));
    newnode->data=num;
    newNode->left=NULL;
    newNode->right=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 if(num>root->data)
    {
        root->right=insert(root->right,num);
    }
    return root;
}
bool search(Node* root,int k)
{
    if(root == NULL)
    {
        return false;
    }
    else if(root->data == k)
    {
        return true;
    }
    else if(k<root->data)
    {
        return search(root->left,k);
    }
    else
    {
        return search(root->right,k);
    }
}
int main()
{
    int size,num,i,k;
    scanf("%d",&size);
    if(size<=0)
    {
        printf("Invalid input");
        return 0;
    }
    for(i=1;i<=size;i++)
    {
        scanf("%d",&num);
        root=insert(root,num);
    }
    scanf("%d",&k);
    if(search(root,k)==true)
    {
        printf("Found");
    }
    else
    {
        printf("Not found");
    }
    return 0;
}