#include<stdio.h>
#include<stdlib.h>
struct node
{
    int data;
    struct node* left;
    struct node* right;
};
struct node* createnode(int val)
{
    struct node* newnode=(struct node*)malloc(sizeof(struct node));
    newnode->data=val;
    newnode->left=newnode->right=NULL;
    return newnode;
}
struct node* insert(struct node* root,int val)
{
    if(root->data==NULL)
    {
        return createnode(val);
    }
    if(val<root->data)
    {
        root->left=insert(root->left,val);
    }
    else if(val>root->data)
    {
        root->right=insert(root->right,val);
    }
    return root;
}
struct node* search(struct node*root,int tar)
{
    if(root==NULL)
    {
        return 0;
    }
    if(tar==root->data)
    {
        return 1;
    }
    else if(tar<root->data)
    {
        return search(root->left,tar);
    }
    else
    {
        return search(root->right,tar);
    }
}
int main()
{
    int n,tar;
    scanf("%d",&n);
    if(n<0)
    {
        printf("Invalid input\n");
        return 0;
    }
    struct node* root=NULL;
    for(int i=0;i<n;i++)
    {
        int val;
        scanf("%d",&val);
        root=insert(root,val);
    }
    scanf("%d",&tar);
    if(tar<0)
    {
        printf("Invalid input\n");
        return 0;
    }
    if(search(root,tar))
    {
        printf("Found\n");
    }
    else
    {
        printf("Not found\n");
    }
    return 0;
}