#include <stdio.h>
#include <stdlib.h>
typedef struct treenode{
    int data;
    struct treenode*left;
    struct treenode*right;
    
}node;
node*root=NULL;
node*create(int num){
          node*newnode=(node*)malloc(sizeof(node));
          newnode->data=num;
          newnode->left=newnode->right=NULL;
          return newnode;
      }
node*insertBST(node*root,int num){
        if(root==NULL)
             return create(num);
        if(num<root->data)
             root->left=insertBST(root->left,num);
        else
            root->right=insertBST(root->right,num);
      
        return root;
}
int countnodes(node*root){
    while(root!=NULL){
        root=root->left;
            if(root->left==NULL){
                printf("%d",root->data);
                break ;
            }
        }
    }

int main(){
    int size,val,num,i;
    node*root=NULL;
    scanf("%d",&size);
    scanf("%d",&val);
    if(size<0){
        printf("Invalid input");
        return 0;
    }
 
    for(i=0;i<size;i++){
        if(!scan("%d",&num)){
            printf("Invalid input");
        }
        root=insertBST(root,num);
    }
    countnodes(root);
       return 0;
}