#include <bits/stdc++.h>
using namespace std;
//Soltan Cristian
#define ll long long
#define all(x) x.begin(), x.end()
#define mod 1000000007
#define pb push_back
#define st first
#define nd second
#define sz(x) (ll)x.size()
#define rall(x) x.rbegin(), x.rend()

const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};
// string __fname = "hamilton"; 
// ifstream in (__fname + ".in"); 
// ofstream out (__fname + ".out"); 
// #define cin in 
// #define cout out



void solve(){

// }  
 

int main()
{   
    ios_base::sync_with_stdio(0); cin.tie(0); cout << fixed  << setprecision(10); 
    // int t;
    // cin >> t;
    // while(t--)
        solve();
    return 0;
}