Problem p02679 (C++) — buggy submission, verdict: Runtime Error

/**
 *    author:  otera
 **/
#include <algorithm>
#include <bitset>
#include <cassert>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>
using namespace std;

#define int long long
typedef long long ll;
typedef unsigned long long ul;
typedef unsigned int ui;
typedef long double ld;
const int inf = 1e9 + 7;
const ll INF = 1LL << 60;
const ll mod = 1e9 + 7;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<int, int> P;
typedef pair<ld, ld> LDP;
typedef pair<ll, ll> LP;
#define fr first
#define sc second
#define all(c) c.begin(), c.end()
#define pb push_back
#define debug(x) cerr << #x << " = " << (x) << endl;
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}

// modint: mod 計算を int を扱うように扱える構造体
template <int MOD> struct Fp {
  long long val;
  constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
    if (val < 0)
      val += MOD;
  }
  constexpr int getmod() { return MOD; }
  constexpr Fp operator-() const noexcept { return val ? MOD - val : 0; }
  constexpr Fp operator+(const Fp &r) const noexcept { return Fp(*this) += r; }
  constexpr Fp operator-(const Fp &r) const noexcept { return Fp(*this) -= r; }
  constexpr Fp operator*(const Fp &r) const noexcept { return Fp(*this) *= r; }
  constexpr Fp operator/(const Fp &r) const noexcept { return Fp(*this) /= r; }
  constexpr Fp &operator+=(const Fp &r) noexcept {
    val += r.val;
    if (val >= MOD)
      val -= MOD;
    return *this;
  }
  constexpr Fp &operator-=(const Fp &r) noexcept {
    val -= r.val;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr Fp &operator*=(const Fp &r) noexcept {
    val = val * r.val % MOD;
    return *this;
  }
  constexpr Fp &operator/=(const Fp &r) noexcept {
    long long a = r.val, b = MOD, u = 1, v = 0;
    while (b) {
      long long t = a / b;
      a -= t * b;
      swap(a, b);
      u -= t * v;
      swap(u, v);
    }
    val = val * u % MOD;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr bool operator==(const Fp &r) const noexcept {
    return this->val == r.val;
  }
  constexpr bool operator!=(const Fp &r) const noexcept {
    return this->val != r.val;
  }
  friend constexpr ostream &operator<<(ostream &os, const Fp<MOD> &x) noexcept {
    return os << x.val;
  }
  friend constexpr istream &operator>>(istream &is, Fp<MOD> &x) noexcept {
    return is >> x.val;
  }
  friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
    if (n == 0)
      return 1;
    auto t = modpow(a, n / 2);
    t = t * t;
    if (n & 1)
      t = t * a;
    return t;
  }
};

// 二項係数ライブラリ
template <class T> struct BiCoef {
  vector<T> fact_, inv_, finv_;
  constexpr BiCoef() {}
  constexpr BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) {
    init(n);
  }
  constexpr void init(int n) noexcept {
    fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1);
    int MOD = fact_[0].getmod();
    for (int i = 2; i < n; i++) {
      fact_[i] = fact_[i - 1] * i;
      inv_[i] = -inv_[MOD % i] * (MOD / i);
      finv_[i] = finv_[i - 1] * inv_[i];
    }
  }
  constexpr T com(int n, int k) const noexcept {
    if (n < k || n < 0 || k < 0)
      return 0;
    return fact_[n] * finv_[k] * finv_[n - k];
  }
  constexpr T fact(int n) const noexcept {
    if (n < 0)
      return 0;
    return fact_[n];
  }
  constexpr T inv(int n) const noexcept {
    if (n < 0)
      return 0;
    return inv_[n];
  }
  constexpr T finv(int n) const noexcept {
    if (n < 0)
      return 0;
    return finv_[n];
  }
};

const int MOD = 1000000007;
// const int MOD = 998244353;
using mint = Fp<MOD>;
BiCoef<mint> bc;

int gcd(int x, int y) {
  if (x < 0)
    x = -x;
  if (y < 0)
    y = -y;
  if (y == 0)
    return x;
  return gcd(y, x % y);
}

void solve() {
  int n;
  cin >> n;
  bc.init(400400);
  vector<int> a(n), b(n);
  map<P, int> mp;
  int cnt00 = 0, cnt01 = 0, cnt10 = 0;
  rep(i, n) {
    cin >> a[i] >> b[i];
    int d = gcd(a[i], b[i]);
    if (d != 0) {
      a[i] /= d;
      b[i] /= d;
    }
    if (a[i] <= 0 && b[i] <= 0) {
      a[i] = -a[i], b[i] = -b[i];
    }
    if (a[i] <= 0 && b[i] >= 0) {
      a[i] = -a[i], b[i] = -b[i];
    }
    //
    if (a[i] == 0 && b[i] == 0) {
      ++cnt00;
    } else if (a[i] == 0) {
      ++cnt01;
    } else if (b[i] == 0) {
      ++cnt10;
    }
    //
    // cerr << a[i] << " " << b[i] << endl;
    // cerr << cnt00 << " " << cnt01 << " " << cnt10 << endl;
    mp[{a[i], b[i]}]++;
  }
  mint ans = (mint)1;
  for (auto p : mp) {
    if (p.fr.sc > 0) {
      if (p.fr.fr == 0)
        continue;
      int co = mp[{p.fr.sc, -p.fr.fr}];
      if (co == 0 || (co > 0 && p.sc > 0))
        ans *= (modpow((mint)2, co) + modpow((mint)2, p.sc) - (mint)1);
      // cerr << co << " " << p.sc << endl;
    } else if (p.fr.sc < 0) {
      if (p.fr.fr == 0)
        continue;
      int co = mp[{-p.fr.sc, p.fr.fr}];
      if (co > 0)
        continue;
      if (co == 0)
        ans *= (modpow((mint)2, co) + modpow((mint)2, p.sc) - (mint)1);
      // cerr << co << " " << p.sc << endl;
    } else if (p.fr.sc == 0) {
      //
    }
  }
  ans *= (modpow((mint)2, cnt01) + modpow((mint)2, cnt10) - (mint)1);
  if (cnt00 > 0) {
    ans += (mint)cnt00;
  }
  ans -= (mint)1; // 空集合
  cout << ans << endl;
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  // cout << fixed << setprecision(10);
  // int t; cin >> t; rep(i, t)solve();
  solve();
  return 0;
}

Error: 0

Fixed submission:

/**
 *    author:  otera
 **/
#include <algorithm>
#include <bitset>
#include <cassert>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>
using namespace std;

#define int long long
typedef long long ll;
typedef unsigned long long ul;
typedef unsigned int ui;
typedef long double ld;
const int inf = 1e9 + 7;
const ll INF = 1LL << 60;
const ll mod = 1e9 + 7;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<int, int> P;
typedef pair<ld, ld> LDP;
typedef pair<ll, ll> LP;
#define fr first
#define sc second
#define all(c) c.begin(), c.end()
#define pb push_back
#define debug(x) cerr << #x << " = " << (x) << endl;
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}

// modint: mod 計算を int を扱うように扱える構造体
template <int MOD> struct Fp {
  long long val;
  constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
    if (val < 0)
      val += MOD;
  }
  constexpr int getmod() { return MOD; }
  constexpr Fp operator-() const noexcept { return val ? MOD - val : 0; }
  constexpr Fp operator+(const Fp &r) const noexcept { return Fp(*this) += r; }
  constexpr Fp operator-(const Fp &r) const noexcept { return Fp(*this) -= r; }
  constexpr Fp operator*(const Fp &r) const noexcept { return Fp(*this) *= r; }
  constexpr Fp operator/(const Fp &r) const noexcept { return Fp(*this) /= r; }
  constexpr Fp &operator+=(const Fp &r) noexcept {
    val += r.val;
    if (val >= MOD)
      val -= MOD;
    return *this;
  }
  constexpr Fp &operator-=(const Fp &r) noexcept {
    val -= r.val;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr Fp &operator*=(const Fp &r) noexcept {
    val = val * r.val % MOD;
    return *this;
  }
  constexpr Fp &operator/=(const Fp &r) noexcept {
    long long a = r.val, b = MOD, u = 1, v = 0;
    while (b) {
      long long t = a / b;
      a -= t * b;
      swap(a, b);
      u -= t * v;
      swap(u, v);
    }
    val = val * u % MOD;
    if (val < 0)
      val += MOD;
    return *this;
  }
  constexpr bool operator==(const Fp &r) const noexcept {
    return this->val == r.val;
  }
  constexpr bool operator!=(const Fp &r) const noexcept {
    return this->val != r.val;
  }
  friend constexpr ostream &operator<<(ostream &os, const Fp<MOD> &x) noexcept {
    return os << x.val;
  }
  friend constexpr istream &operator>>(istream &is, Fp<MOD> &x) noexcept {
    return is >> x.val;
  }
  friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
    if (n == 0)
      return 1;
    auto t = modpow(a, n / 2);
    t = t * t;
    if (n & 1)
      t = t * a;
    return t;
  }
};

// 二項係数ライブラリ
template <class T> struct BiCoef {
  vector<T> fact_, inv_, finv_;
  constexpr BiCoef() {}
  constexpr BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) {
    init(n);
  }
  constexpr void init(int n) noexcept {
    fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1);
    int MOD = fact_[0].getmod();
    for (int i = 2; i < n; i++) {
      fact_[i] = fact_[i - 1] * i;
      inv_[i] = -inv_[MOD % i] * (MOD / i);
      finv_[i] = finv_[i - 1] * inv_[i];
    }
  }
  constexpr T com(int n, int k) const noexcept {
    if (n < k || n < 0 || k < 0)
      return 0;
    return fact_[n] * finv_[k] * finv_[n - k];
  }
  constexpr T fact(int n) const noexcept {
    if (n < 0)
      return 0;
    return fact_[n];
  }
  constexpr T inv(int n) const noexcept {
    if (n < 0)
      return 0;
    return inv_[n];
  }
  constexpr T finv(int n) const noexcept {
    if (n < 0)
      return 0;
    return finv_[n];
  }
};

const int MOD = 1000000007;
// const int MOD = 998244353;
using mint = Fp<MOD>;
BiCoef<mint> bc;

int gcd(int x, int y) {
  if (x < 0)
    x = -x;
  if (y < 0)
    y = -y;
  if (y == 0)
    return x;
  return gcd(y, x % y);
}

void solve() {
  int n;
  cin >> n;
  bc.init(400400);
  vector<int> a(n), b(n);
  map<P, int> mp;
  int cnt00 = 0, cnt01 = 0, cnt10 = 0;
  rep(i, n) {
    cin >> a[i] >> b[i];
    int d = gcd(a[i], b[i]);
    a[i] /= d, b[i] /= d;
    if (a[i] <= 0 && b[i] <= 0) {
      a[i] = -a[i], b[i] = -b[i];
    }
    if (a[i] <= 0 && b[i] >= 0) {
      a[i] = -a[i], b[i] = -b[i];
    }
    //
    if (a[i] == 0 && b[i] == 0) {
      ++cnt00;
    } else if (a[i] == 0) {
      ++cnt01;
    } else if (b[i] == 0) {
      ++cnt10;
    }
    //
    // cerr << a[i] << " " << b[i] << endl;
    mp[{a[i], b[i]}]++;
  }
  mint ans = (mint)1;
  for (auto p : mp) {
    if (p.fr.sc > 0) {
      int co = mp[{p.fr.sc, -p.fr.fr}];
      if (co == 0 || (co > 0 && p.sc > 0))
        ans *= (modpow((mint)2, co) + modpow((mint)2, p.sc) - (mint)1);
      // cerr << co << " " << p.sc << endl;
    } else if (p.fr.sc < 0) {
      int co = mp[{-p.fr.sc, p.fr.fr}];
      if (co > 0)
        continue;
      if (co == 0)
        ans *= (modpow((mint)2, co) + modpow((mint)2, p.sc) - (mint)1);
      // cerr << co << " " << p.sc << endl;
    } else if (p.fr.sc == 0) {
      //
    }
  }
  ans *= (modpow((mint)2, cnt01) + modpow((mint)2, cnt10) - (mint)1);
  if (cnt00 > 0) {
    ans += (mint)cnt00;
  }
  ans -= (mint)1; // 空集合
  cout << ans << endl;
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  // cout << fixed << setprecision(10);
  // int t; cin >> t; rep(i, t)solve();
  solve();
  return 0;
}