#include <bits/stdc++.h>
template <class T>
bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
using namespace std;
using uif = uint_fast64_t;
using ll = long long int;
int qp(int a, ll b) {
  int ans = 1;
  do {
    if (b & 1) ans = 1ll * ans * a % 1000000007;
    a = 1ll * a * a % 1000000007;
  } while (b >>= 1);
  return ans;
}
int qp(int a, ll b, int mo) {
  int ans = 1;
  do {
    if (b & 1) ans = 1ll * ans * a % mo;
    a = 1ll * a * a % mo;
  } while (b >>= 1);
  return ans;
}
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int main(void) {
  ll n, m, s, t;
  cin >> n >> m >> s >> t;
  vector<ll> u(m);
  vector<ll> v(m);
  vector<ll> a(m);
  vector<ll> b(m);
  return 0;
}
