#include <algorithm>
#include <bitset>
#include <cassert>
#include <climits>
#include <cmath>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <tuple>
#include <vector>
#define sz(c) ((int)c.size())
#define trav(it, c) for (auto it : c)
#define rep(var, begin, end) for (int var = begin; var < end; ++var)
#define forn(i, n) for (int i = 0; i < n; ++i)
#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()
#define compress(c) (sort(all(c)), c.erase(unique(all(c)), c.end()))
#define emb emplace_back
#define psb push_back
using namespace std;
using ll = long long;
using ii = pair<int, int>;
using vi = vector<int>;
using vii = vector<ii>;
const int mod = 1e9 + 7;
const string file_base = "";

int add(int a, int b, int m = mod) {
    return a + b < m ? a + b : a + b - m;
}

int mul(ll a, ll b, int m = mod) {
    return a * b % m;
}

int ex(int a, int b, int m = mod) {
    int r=1;
    for (; b>0; b/=2, a=mul(a,a,m))
        if (b&1) r = mul(r, a, m);
    return r;
}

const int inf = 1.2e9;

struct Solver {
    bool solve_one(istream &in, ostream &out) {

        return 0;
    }
    void solve(istream &in, ostream &out) {
        out.precision(10);
        out << fixed;
        int test_number = 1;
        //in >> test_number;
        forn(tc, test_number) {
            //out << "Case #" << tc+1 << ": ";
            if (solve_one(in, out)) break;
        }
    }
};

int main() {
    Solver solver;
    if (!file_base.empty()) {
        ifstream in(file_base + ".in");
        ofstream out(file_base + ".out");
        in.exceptions(in.failbit);
        solver.solve(in, out);
    } else {
        cin.tie(nullptr)->sync_with_stdio(false);
        //cin.exceptions(cin.failbit);
        solver.solve(cin, cout);
    }
    return 0;
}