#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){
        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 root;
    }
}
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);
    else
         return search(root->right,target);
}
int main()
{
    int n,value,target;
    scanf("%d",&n);
    if(n<0){
        printf("Invalid input\n");
        return 0;
    }
    struct Node* root=NULL;
    for(int i=0;i<n;i++){
        scanf("%d",&value);
        root=insert(root,value);
    }
    scanf("%d",&target);
    
    if(target<0){
        printf("Invalid input\n");
        return 0;
    }
    if(search(root,target))
         printf("Found\n");
    else
        print("Not found\n");
    return 0; 
    
    
    
}