#include <bits/stdc++.h>
#define tt int tt;cin>>tt;while(tt--)
#define ll long long
#define mod 1000000007
#define cin(vec) for(auto& i : vec) cin >> i
#define cout(vec) for(auto& i : vec) cout<< i<<" ";
const double eps = 1e-7;
using namespace std;
void fast() {
ios_base::sync_with_stdio(false);
cout.tie(null);
cin.tie(null);
}
struct node{
int data;
node*next;
};
class lin{
node*last;
public:
lin(){
last=null;
}
void creat_node(int item){
if(last!=null){
return ;
}
node*new_node=new node;
last=new node;
last->data=item;
last->next=last;
}
void insert_front(int item){
if(last==null){
creat_node(item);return;
}
node*new_node=new node;
new_node->data=item;
new_node->next=last->next;
last->next=new_node;
}
void insert_back(int i){
if(last==null){
creat_node(i);return;
}
node*new_node=new node;
new_node->data=i;
last->next=new_node;
new_node->next=last->next;
}
void insrt_pos(int pos,int i){
node*new_node=new node;
new_node->data=i;
node*curr=last->next;
for(int i=0;i<pos-1;i++){
curr=curr->next;
}
new_node->next=curr->next;
curr->next=new_node;
if(curr==last)last=new_node;
}
void display(){
node*temp=new node;
temp=last->next;
while(temp!=last){
cout<<temp->data<<" ";
temp=temp->next;
}
cout<<last->data;
}
};
int main() {
fast();
}