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