#include<stdio.h>
#include<stdlib.h>

struct TreeNode{
    int data;
    struct TreeNode*left,*right;
    
};

struct TreeNode*createNode(int value){
    struct TreeNode*node=(struct TreeNode*)malloc(sizeof(struct TreeNode));
    node->data=value;
    node->left=node->right=NULL;
    return node;
}

struct TreeNode*insert(struct TreeNode*root,int value){
    if(root==NULL)return
    createNode(value);
    if(value<root->data)
    root->left=insert(root->left,value);
    else
    root->right=insert(root->right,value);
    return root;
}

intsearch(struct TreeNode*root,int target){
    if(root==NULL)return 0;
    if(root->data==target)return 1;
    if(target<root->data)return search(root->left,target);
    else
    return search(root->right,target);
}

int main(){
    int n;
    if(scanf("%d",&n)!=1)return 0;
    
    
    if(n<=0){
        printf("invalid input");
        return 0;
    
}


struct TreeNode*root=NULL;
int val,target;

for(int i=0;i<n;i++){
    scanf("%d",&val);
}

scanf("%d",&target);

if(search(root,target))
printf("found");
else
print("not found");
return 0;
}