Submission #2702367

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
#ifdef _DEBUG
#define _GLIBCXX_DEBUG
#include "dump.hpp"
#else
#define dump(...)
#endif

#define int long long
// typedef __int128_t Int;
#define DBG 1
#define rep(i, a, b) for (int i = (a); i < (b); i++)
#define rrep(i, a, b) for (int i = (b)-1; i >= (a); i--)
#define loop(n) rep(loop, (0), (n))
#define all(c) begin(c), end(c)
const int INF =
    sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;
const int MOD = (int)(1e9) + 7;
const double PI = acos(-1);
const double EPS = 1e-9;
template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}

signed main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(12);

  int N;
  cin >> N;
  vector<int> a(N);
  rep(i, 0, N) { cin >> a[i]; }
  vector<int> b(N);
  rep(i, 0, N) { cin >> b[i]; }
  vector<pair<int, int>> v;
  rep(i, 0, N) { v.push_back(make_pair(a[i], 0)); }
  rep(i, 0, N) { v.push_back(make_pair(b[i], 1)); }
  sort(all(v));
  dump(v);

  int cnta = 0, cntb = 0, ans = 1;
  rep(i, 0, 2*N) {
    if (v[i].second == 0) {
      if (cntb > 0) {
        (ans *= cntb) %= MOD;
        cntb--;
      } else
        cnta++;
    } else {
      if (cnta > 0) {
        (ans *= cnta) %= MOD;
        cnta--;
      } else
        cntb++;
    }
    dump(ans,cnta,cntb);
  }
  cout << ans << endl;

  return 0;
}

Submission Info

Judge Result