Submission #329655

#	Time	Username	Problem	Language	Result	Execution time	Memory
329655		VROOM_VARUN	Tents (JOI18_tents)	C++14	100 / 100	86 ms	70892 KiB

tents

/*
ID: varunra2
LANG: C++
TASK: tents
*/

#include <bits/stdc++.h>
using namespace std;

#define int long long

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

int32_t main() {
// #ifndef ONLINE_JUDGE
  // freopen("tents.in", "r", stdin);
  // freopen("tents.out", "w", stdout);
// #endif
  cin.sync_with_stdio(0);
  cin.tie(0);

  int n, m;

  cin >> n >> m;

  VVI dp(n + 1, VI(m + 1, 1));

  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      dp[i][j] = dp[i - 1][j];
      if (j >= 2) {
        dp[i][j] += dp[i - 1][j - 2] * (j * (j - 1)) / 2;
      }
      if (i >= 2) dp[i][j] += dp[i - 2][j - 1] * j * (i - 1);
      dp[i][j] += 4 * j * dp[i - 1][j - 1];
      dp[i][j] %= MOD;
    }
  }

  cout << dp[n][m] - 1 << '\n';

  return 0;
}

• Subtask 1: 48 / 48
• Subtask 2: 52 / 52