#include<stdio.h>
#include<stdlib.h>
struct node{
    int data;
    struct node* left;
    struct node* right;
};
struct node* create(int data)
{
    struct node* newnode=(struct node*)malloc(sizeof(struct node));
    if(!newnode){
        printf("Memory allocation failed\n");
        exit(1);
    }   
    newnode->data = data;
    newnode->left = newnode->right=NULL;
    return newnode;
}
struct node* insert(struct node* root,int data){
    if(root == NULL)
    return create(data);
    
    if(data < root->data)
    root->left = insert(root->left, data);
    else if(data > root->data)
    root->right=insert(root->right, data);
    return root;
}
int search(struct node* root,int key){
    if(root == NULL)
    return 0;
    
    if(root->data == key)
    return 1;
    else if(key < root->data)
    return search(root->left,key);
    else
    return search(root->right,key);
    }
int main()
{
    int n,value,key;
    if(scanf("%d",&n)!=1){
        printf("Invalid input\n");
        return 0;
    }
    if(n <= 0||n<-10||n>10){
        printf("Invalid input");
        return 0;
    }
struct node* root=NULL;
for(int i=0;i<n;i++)
{
    if(scanf("%d",&value) !=1){
        printf("Invalid input");
        return 0;
    }
    root=insert(root, value);
}
if(scanf("%d",&key)!=1){
    printf("Invalid input");
    return 0;
}
if(search(root, key))
printf("Found\n");
else
printf("Not Found\n");
return 0;
}