Problem p03674 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define REP(i, n) for (int i = 1; i < (int)(n); i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define vout(x) rep(i, x.size()) cout << x[i] << " "
template <class T> bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
using namespace std;
using vint = vector<int>;
using vvint = vector<vector<int>>;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vector<ll>>;
using P = pair<ll, int>;
const int inf = 1e9;
const ll inf_l = 1e18;
const int MAX = 1e5;

// mod(1e9+7)
const ll mod = 1e9 + 7;
struct mint {
  ll x;
  mint(ll x = 0) : x(x % mod) {}
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
};

// nCr
struct com {
  ll MAX;
  ll mod;
  vll fac, finv, inv;
  com(ll n, ll MOD) {
    mod = MOD;
    COMinit(n);
  }
  void COMinit(ll n) {
    MAX = n;
    fac.resize(MAX);
    finv.resize(MAX);
    inv.resize(MAX);
    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;
    }
  }

  ll cal(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;
  }
};

int main() {
  int n;
  cin >> n;
  map<int, int> ct;
  vint a(n + 1);
  rep(i, n + 1) {
    int a_;
    cin >> a_;
    ct[a_]++;
    a[i] = a_;
  }
  int x;
  for (auto itr = ct.begin(); itr != ct.end(); itr++) {
    if (itr->second == 2)
      x = itr->first;
  }
  int len_r;
  for (int i = n; i >= 0; i--) {
    if (a[i] == x) {
      len_r = n - i;
      break;
    }
  }
  int len_l;
  for (int i = 0; i <= n; i++) {
    if (a[i] == x) {
      len_l = i;
      break;
    }
  }
  if (len_l > len_r)
    swap(len_l, len_r);
  // cout << len_l << len_r << endl;
  com cm(MAX + 5, mod);
  REP(i, n + 2) {
    mint tmp;
    tmp = cm.cal(n + 1, i);
    if (i == 1)
      tmp -= 1;
    else
      rep(j, min(i, len_l + 1)) tmp -=
          cm.cal(len_l, j) * cm.cal(len_r, i - 1 - j);
    printf("%lld\n", tmp.x);
  }
}

Fixed submission:
#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define REP(i, n) for (int i = 1; i < (int)(n); i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define vout(x) rep(i, x.size()) cout << x[i] << " "
template <class T> bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
using namespace std;
using vint = vector<int>;
using vvint = vector<vector<int>>;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vector<ll>>;
using P = pair<ll, int>;
const int inf = 1e9;
const ll inf_l = 1e18;
const int MAX = 1e5;

// mod(1e9+7)
const ll mod = 1e9 + 7;
struct mint {
  ll x;
  mint(ll x = 0) : x(x % mod) {}
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
};

// nCr
struct com {
  ll MAX;
  ll mod;
  vll fac, finv, inv;
  com(ll n, ll MOD) {
    mod = MOD;
    COMinit(n);
  }
  void COMinit(ll n) {
    MAX = n;
    fac.resize(MAX);
    finv.resize(MAX);
    inv.resize(MAX);
    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;
    }
  }

  ll cal(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;
  }
};

int main() {
  int n;
  cin >> n;
  map<int, int> ct;
  vint a(n + 1);
  rep(i, n + 1) {
    int a_;
    cin >> a_;
    ct[a_]++;
    a[i] = a_;
  }
  int x;
  for (auto itr = ct.begin(); itr != ct.end(); itr++) {
    if (itr->second == 2)
      x = itr->first;
  }
  int len_r;
  for (int i = n; i >= 0; i--) {
    if (a[i] == x) {
      len_r = n - i;
      break;
    }
  }
  int len_l;
  for (int i = 0; i <= n; i++) {
    if (a[i] == x) {
      len_l = i;
      break;
    }
  }
  if (len_l > len_r)
    swap(len_l, len_r);
  // cout << len_l << len_r << endl;
  com cm(MAX + 5, mod);
  REP(i, n + 2) {
    mint tmp;
    tmp = cm.cal(n + 1, i);
    if (i == 1)
      tmp -= 1;
    else
      tmp -= cm.cal(len_l + len_r, i - 1);
    printf("%lld\n", tmp.x);
  }
}