Problem p02634 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
using namespace std;
#define FOR(i, l, r) for (long long i = (l); i < (r); ++i)
#define REP(i, n) FOR(i, 0, n)
#define REPS(i, n) FOR(i, 1, n + 1)
#define RFOR(i, l, r) for (long long i = (l); i >= (r); --i)
#define RREP(i, n) RFOR(i, n - 1, 0)
#define RREPS(i, n) RFOR(i, n, 1)
#define int long long
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define SZ(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
const int INF = 1e18;
const int MOD = 998244353;
const int MAX = 1000010;
int fac[MAX], finv[MAX], inv[MAX];

// テーブル作成
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < MAX; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}

// nCkを求める
int COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

// ModInt
template <typename T> T pow(T a, long long n, T e = 1) {
  T ret = e;
  while (n) {
    if (n & 1)
      ret *= a;
    a *= a;
    n >>= 1;
  }
  return ret;
}

template <int mod> struct ModInt {
  int x;
  ModInt() : x(0) {}
  ModInt(long long x_) {
    if ((x = x_ % mod + mod) >= mod)
      x -= mod;
  }
  ModInt &operator+=(ModInt rhs) {
    if ((x += rhs.x) >= mod)
      x -= mod;
    return *this;
  }
  ModInt &operator-=(ModInt rhs) {
    if ((x -= rhs.x) < 0)
      x += mod;
    return *this;
  }
  ModInt &operator*=(ModInt rhs) {
    x = (unsigned long long)x * rhs.x % mod;
    return *this;
  }
  ModInt &operator/=(ModInt rhs) {
    x = (unsigned long long)x * rhs.inv().x % mod;
    return *this;
  }

  ModInt operator-() const { return -x < 0 ? mod - x : -x; }
  ModInt operator+(ModInt rhs) const { return ModInt(*this) += rhs; }
  ModInt operator-(ModInt rhs) const { return ModInt(*this) -= rhs; }
  ModInt operator*(ModInt rhs) const { return ModInt(*this) *= rhs; }
  ModInt operator/(ModInt rhs) const { return ModInt(*this) /= rhs; }
  bool operator==(ModInt rhs) const { return x == rhs.x; }
  bool operator!=(ModInt rhs) const { return x != rhs.x; }
  ModInt inv() const { return pow(*this, mod - 2); }

  friend ostream &operator<<(ostream &s, ModInt<mod> a) {
    s << a.x;
    return s;
  }
  friend istream &operator>>(istream &s, ModInt<mod> &a) {
    s >> a.x;
    return s;
  }
};
using mint = ModInt<MOD>;

signed main() {
  int a, b, c, d;
  cin >> a >> b >> c >> d;
  int k = c + d - a - b;
  vector<vector<mint>> dp(c - a + 1, vector<mint>(d - b + 1, (mint)0));
  dp[0][0] = 1; // dp[a][b]は縦a個横b個数チョイス済み
  REPS(i, k) {
    REP(j, i + 1) {
      if (i - j < 0 or i - j > c - a or j > d - b)
        continue;
      dp[i - j][j] =
          (i - j - 1 > -1 ? dp[i - j - 1][j] : (mint)0) * (mint)(b + j) +
          (j - 1 > -1 ? dp[i - j][j - 1] : (mint)0) * (mint)(a + i - j);
      if (i - j - 1 > -1 and j - 1 > -1)
        dp[i - j][j] -=
            dp[i - j - 1][j - 1] * (mint)(a + i - j - 1) * (mint)(b + j - 1);
    }
  }
  cout << dp[c - a][d - b] << endl;
}

Error: -11

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
#define FOR(i, l, r) for (long long i = (l); i < (r); ++i)
#define REP(i, n) FOR(i, 0, n)
#define REPS(i, n) FOR(i, 1, n + 1)
#define RFOR(i, l, r) for (long long i = (l); i >= (r); --i)
#define RREP(i, n) RFOR(i, n - 1, 0)
#define RREPS(i, n) RFOR(i, n, 1)
#define int long long
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define SZ(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
const int INF = 1e18;
const int MOD = 998244353;
const int MAX = 1000010;
int fac[MAX], finv[MAX], inv[MAX];

// テーブル作成
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < MAX; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}

// nCkを求める
int COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

// ModInt
template <typename T> T pow(T a, long long n, T e = 1) {
  T ret = e;
  while (n) {
    if (n & 1)
      ret *= a;
    a *= a;
    n >>= 1;
  }
  return ret;
}

template <int mod> struct ModInt {
  int x;
  ModInt() : x(0) {}
  ModInt(long long x_) {
    if ((x = x_ % mod + mod) >= mod)
      x -= mod;
  }
  ModInt &operator+=(ModInt rhs) {
    if ((x += rhs.x) >= mod)
      x -= mod;
    return *this;
  }
  ModInt &operator-=(ModInt rhs) {
    if ((x -= rhs.x) < 0)
      x += mod;
    return *this;
  }
  ModInt &operator*=(ModInt rhs) {
    x = (unsigned long long)x * rhs.x % mod;
    return *this;
  }
  ModInt &operator/=(ModInt rhs) {
    x = (unsigned long long)x * rhs.inv().x % mod;
    return *this;
  }

  ModInt operator-() const { return -x < 0 ? mod - x : -x; }
  ModInt operator+(ModInt rhs) const { return ModInt(*this) += rhs; }
  ModInt operator-(ModInt rhs) const { return ModInt(*this) -= rhs; }
  ModInt operator*(ModInt rhs) const { return ModInt(*this) *= rhs; }
  ModInt operator/(ModInt rhs) const { return ModInt(*this) /= rhs; }
  bool operator==(ModInt rhs) const { return x == rhs.x; }
  bool operator!=(ModInt rhs) const { return x != rhs.x; }
  ModInt inv() const { return pow(*this, mod - 2); }

  friend ostream &operator<<(ostream &s, ModInt<mod> a) {
    s << a.x;
    return s;
  }
  friend istream &operator>>(istream &s, ModInt<mod> &a) {
    s >> a.x;
    return s;
  }
};
using mint = ModInt<MOD>;
mint dp[4000][4000];

signed main() {
  int a, b, c, d;
  cin >> a >> b >> c >> d;
  int k = c + d - a - b;
  dp[0][0] = 1; // dp[a][b]は縦a個横b個数チョイス済み
  REPS(i, k) {
    REP(j, 3000) {
      if (i - j < 0)
        continue;
      dp[i - j][j] =
          (i - j - 1 > -1 ? dp[i - j - 1][j] : (mint)0) * (mint)(b + j) +
          (j - 1 > -1 ? dp[i - j][j - 1] : (mint)0) * (mint)(a + i - j);
      if (i - j - 1 > -1 and j - 1 > -1)
        dp[i - j][j] -=
            dp[i - j - 1][j - 1] * (mint)(a + i - j - 1) * (mint)(b + j - 1);
    }
  }
  cout << dp[c - a][d - b] << endl;
}