#include
using namespace std;
class node{
public:
int data;
node * next;
node(int d){
data = d;
next = NULL;
}
};
void create_list(node *& head , int data){
if(head == NULL){
head = new node(data);
}
else{
node * temp = head;
while(temp->next!=NULL){
temp = temp->next;
}
temp = new node(data);
}
}
void move_k_steps(node *& fast , int k){
while(k–){
fast = fast->next;
}
}
void last_k_element(node * head, int k){
node * fast = head;
node * slow = head;
move_k_steps(fast , k);
while(fast != NULL){
fast = fast->next;
slow = slow->next;
}
cout<data<<endl;
}
int main() {
node * head = NULL;
int n;
cin>>n;
while(n != -1){
create_list(head , n);
cin>>n;
}
int k;
cin>>k;
last_k_element(head , k);
return 0;
}