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

// clang-format off
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define stoi stoll
using pii = pair<int,int>;
using vi = vector<int>;
using vvi = vector<vi>;
#define all(c) begin(c), end(c)
#define rall(c) rbegin(c), rend(c)
#define fore(x, c) for(auto &&x : c)
#define rep(i, a, n) for(int i = a, i##len = (int)(n); i < i##len; ++i)
#define rrep(i, a, n) for(int i = (int)(n - 1); i >= a; --i)
#define sz(c) ((int)c.size())
#define contains(c, x) (c.find(x) != end(c))
#define inseg(l, x, r) ((l) <= (x) && (x) < (r))
#define dump(...)
#define pb push_back
#define eb emplace_back
#define _ 0
const signed INF_ = 1001001001; const long long INF = 1001001001001001001LL;
const int DX[9] = {0,1,0,-1,1,1,-1,-1,0}, DY[9] = {-1,0,1,0,-1,1,1,-1,0};
template<class T> ostream& operator<<(ostream &os, const vector<T> &v) {
  for (auto i = begin(v); i != end(v); i++) os<<*i<<(i==end(v)-1?"":" ");return os;}
template<class T> istream& operator>>(istream &is, vector<T> &v) {
  for (auto i = begin(v); i != end(v); i++) is>>*i;return is;}
template<class T,class U> istream& operator>>(istream &is, pair<T,U> &p) {
  is>>p.first>>p.second;return is;}
template<class T, class U> bool chmax(T &a, const U &b){return a<b?a=b,1:0;}
template<class T, class U> bool chmin(T &a, const U &b){return a>b?a=b,1:0;}
template <class T> void psum(T& c) {partial_sum(begin(c), end(c), begin(c));}
template<class T> using heap = priority_queue<T, deque<T>, greater<T>>;
struct before_main_function {
  before_main_function() {
      cin.tie(nullptr); ios::sync_with_stdio(0);
      cout << setprecision(15) << fixed;
  }
} before_main_function;
// clang-format on
//------------------8<------------------------------------8<--------------------

int gcd(int a, int b) { return a ? gcd(b % a, a) : b; }
int lcm(int a, int b) { return a / gcd(a, b) * b; }
const int MOD = 1000000007;
int bin_pow_mod(int a, int b) {
  int ret = 1;
  while (b > 0) {
    if (b & 1)
      ret = (ret * a) % MOD;
    a = (a * a) % MOD;
    b >>= 1;
  }
  return ret;
}
signed main() {
  int N;
  cin >> N;
  vi A(N), B(N);
  rep(i, 0, N) cin >> A[i] >> B[i];
  map<pii, pii> cnt;
  int zero = 0;
  rep(i, 0, N) {
    int a = abs(A[i]), b = abs(B[i]);
    if (a == 0 && b == 0) {
      zero++;
    } else if (a == 0) {
      cnt[pii(0, INF)].first++;
    } else if (b == 0) {
      cnt[pii(0, INF)].second++;
    } else {
      int sign = (A[i] / abs(A[i])) * (B[i] / abs(B[i]));
      int g = gcd(a, b);
      a /= g;
      b /= g;
      (sign > 0 ? cnt[pii(a, b)].first : cnt[pii(b, a)].second)++;
    }
  }
  int ans = 0;
  ans += zero;
  int tmp = 1;
  for (auto &&p : cnt) {
    int x, y;
    tie(x, y) = p.second;
    tmp *= bin_pow_mod(2, x) + bin_pow_mod(2, y) + MOD - 1;
    tmp %= MOD;
  }
  tmp = tmp + MOD - 1;
  ans += tmp;
  ans %= MOD;
  cout << ans << endl;
  return (0 ^ _ ^ 0);
}


Error: 0

Fixed submission:

// clang-format off
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define stoi stoll
using pii = pair<int,int>;
using vi = vector<int>;
using vvi = vector<vi>;
#define all(c) begin(c), end(c)
#define rall(c) rbegin(c), rend(c)
#define fore(x, c) for(auto &&x : c)
#define rep(i, a, n) for(int i = a, i##len = (int)(n); i < i##len; ++i)
#define rrep(i, a, n) for(int i = (int)(n - 1); i >= a; --i)
#define sz(c) ((int)c.size())
#define contains(c, x) (c.find(x) != end(c))
#define inseg(l, x, r) ((l) <= (x) && (x) < (r))
#define dump(...)
#define pb push_back
#define eb emplace_back
#define _ 0
const signed INF_ = 1001001001; const long long INF = 1001001001001001001LL;
const int DX[9] = {0,1,0,-1,1,1,-1,-1,0}, DY[9] = {-1,0,1,0,-1,1,1,-1,0};
template<class T> ostream& operator<<(ostream &os, const vector<T> &v) {
  for (auto i = begin(v); i != end(v); i++) os<<*i<<(i==end(v)-1?"":" ");return os;}
template<class T> istream& operator>>(istream &is, vector<T> &v) {
  for (auto i = begin(v); i != end(v); i++) is>>*i;return is;}
template<class T,class U> istream& operator>>(istream &is, pair<T,U> &p) {
  is>>p.first>>p.second;return is;}
template<class T, class U> bool chmax(T &a, const U &b){return a<b?a=b,1:0;}
template<class T, class U> bool chmin(T &a, const U &b){return a>b?a=b,1:0;}
template <class T> void psum(T& c) {partial_sum(begin(c), end(c), begin(c));}
template<class T> using heap = priority_queue<T, deque<T>, greater<T>>;
struct before_main_function {
  before_main_function() {
      cin.tie(nullptr); ios::sync_with_stdio(0);
      cout << setprecision(15) << fixed;
  }
} before_main_function;
// clang-format on
//------------------8<------------------------------------8<--------------------

int gcd(int a, int b) { return a ? gcd(b % a, a) : b; }
int lcm(int a, int b) { return a / gcd(a, b) * b; }
signed main() {
  int N;
  cin >> N;
  vi A(N), B(N);
  rep(i, 0, N) cin >> A[i] >> B[i];
  map<pii, pii> cnt;
  int zero = 0;
  rep(i, 0, N) {
    int a = abs(A[i]), b = abs(B[i]);
    int sign = A[i] / abs(A[i]) * B[i] / abs(B[i]);
    int g = gcd(a, b);
    a /= g;
    b /= g;
    if (sign > 0)
      swap(a, b);
    if (a == 0 && b == 0) {
      zero++;
    } else if (a == 0) {
      (sign > 0 ? cnt[pii(0, INF)].first : cnt[pii(0, INF)].second)++;
    } else if (b == 0) {
      (sign > 0 ? cnt[pii(INF, 0)].first : cnt[pii(INF, 0)].second)++;
    } else {
      (sign > 0 ? cnt[pii(a, b)].first : cnt[pii(a, b)].second)++;
    }
  }
  int ans = 0;
  const int MOD = 1000000007;
  ans += zero;
  int tmp = 1;
  for (auto &&p : cnt) {
    int x, y;
    tie(x, y) = p.second;
    tmp *= x * (x + 1) / 2 % MOD + y * (y + 1) / 2 % MOD + 1;
    tmp %= MOD;
  }
  tmp = tmp + MOD - 1;
  ans += tmp;
  ans %= MOD;
  cout << ans << endl;
  return (0 ^ _ ^ 0);
}