#include<stdio.h>
#include<stdlib.h>
typedef struct Node {
    int data;
    struct Node *left, *right
}Node;
Node* newNode(int v) {
    Node* p=(Node*)malloc(sizeof(Node));
    p->data=v;
    p->left=p->right=NULL;
    return p;
}
Node* insert(Node* root, int v) {
    if(!root)
        return newNode(v);
    Node *cur=root, *parent=NULL;
    while(cur){
        parent=cur;
        if(v<=cur->data)
            cur=cur->left;
        else
            cur=cur->right;
    }
    if(v<=parent->data)
        parent->left=newNode(v);
    else
        parent->right=newNode(v);
    return root;
}
int search(Node* root, int k) {
    Node* cur=root;
    while(cur) {
        if(cur->data==k)
            return 1;
        cur=(k<cur->data) ? cur->left: cur->right;
    }
    return 0;
}
int main(void) {
    int n;
    if(scanf("%d", &n) != 1)
        return 0;
    if(n<=0) {
        printf("Invalid input");
        return 0;
    }
    Node *root=NULL;
    for(int i=0;i<n;i++) {
        int x;
        if(scanf("%d", &x) != 1)
            x=0;
        root=insert(root, x);
    }
    int target;
    if(scanf("%d", &target) !=1)
        return 0;
    printf(search(root, target) ? "Found" : "Not Found");
    return 0;
}