#include <stdio.h>
#include <stdlib.h>
struct Node {
    int data;
    struct Node *left;
    struct Node *right;
};
struct Node* createNode(int data) {
    struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
    if ( newNode == NULL) {
        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 createNode(data);
    }
    if (data<root->data) {
        root->left = insert(root->left, data);
    } else if(data>root->data){
        root->right = insert(root->right, data);
    return 0;
}
int search(struct Node* root, int target) {
    if (root == NULL) {
        return 0;  
    }
    if (root->data == target) {
        return 1; 
    }
    else if (target < root->data) {
        return search(root->left, target);
    }
    return search(root->right, target);
}

int main() {
    int n,target;
    scanf("%d", &n);

    if (n <= 0) {
        printf("Invalid input\n");
        return 0;
    }

    struct Node* root = NULL;
    int data;
    for (int i = 0; i < n; i++) {
        scanf("%d", &data);
        root = insert(root, value);
    }
    scanf("%d", &target);
    
    if(target<0){
        printf("invalid input\n");
        return 0;
    }
    if (search(root, target)) {
        printf("Found\n");
    } else {
        printf("Not Found\n");
    }