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

#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
// #include<ext/pb_ds/assoc_container.hpp>
// #include<ext/pb_ds/tree_policy.hpp>
// #include<ext/pb_ds/tag_and_trait.hpp>
// using namespace __gnu_pbds;
// #include<boost/multiprecision/cpp_int.hpp>
// namespace multiprecisioninteger = boost::multiprecision;
// using cint=multiprecisioninteger::cpp_int;
using namespace std;
using ll = long long;
#define double long double
using datas = pair<ll, ll>;
using ddatas = pair<double, double>;
using tdata = pair<ll, datas>;
using vec = vector<ll>;
using mat = vector<vec>;
using pvec = vector<datas>;
using pmat = vector<pvec>;
// using
// llset=tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>;
#define For(i, a, b) for (i = a; i < (ll)b; ++i)
#define bFor(i, b, a) for (i = b, --i; i >= (ll)a; --i)
#define rep(i, N) For(i, 0, N)
#define rep1(i, N) For(i, 1, N)
#define brep(i, N) bFor(i, N, 0)
#define brep1(i, N) bFor(i, N, 1)
#define all(v) (v).begin(), (v).end()
#define allr(v) (v).rbegin(), (v).rend()
#define vsort(v) sort(all(v))
#define vrsort(v) sort(allr(v))
#define endl "\\n"
#define eb emplace_back
#define print(v) cout << v << endl
#define printyes cout << "Yes" << endl
#define printno cout << "No" << endl
#define printYES cout << "YES" << endl
#define printNO cout << "NO" << endl
#define output(v)                                                              \\
  do {                                                                         \\
    bool f = 0;                                                                \\
    for (auto outi : v) {                                                      \\
      cout << (f ? " " : "") << outi;                                          \\
      f = 1;                                                                   \\
    }                                                                          \\
    cout << endl;                                                              \\
  } while (0)
#define matoutput(v)                                                           \\
  do {                                                                         \\
    for (auto outimat : v)                                                     \\
      output(outimat);                                                         \\
  } while (0)
const ll mod = 1000000007;
// const ll mod=998244353;
const ll inf = 1LL << 60;
const double PI = acos(-1);
const double eps = 1e-9;
template <class T> inline bool chmax(T &a, T b) {
  bool x = a < b;
  if (x)
    a = b;
  return x;
}
template <class T> inline bool chmin(T &a, T b) {
  bool x = a > b;
  if (x)
    a = b;
  return x;
}

void startupcpp() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(15);
}

double distance(ddatas x, ddatas y) {
  double a = x.first - y.first, b = x.second - y.second;
  return sqrt(a * a + b * b);
}

ll modinv(ll a) {
  ll b = mod, u = 1, v = 0, t;
  while (b) {
    t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  return (u + mod) % mod;
}

ll moddevide(ll a, ll b) { return (a * modinv(b)) % mod; }

vec modncrlistp, modncrlistm;

ll modncr(ll n, ll r) {
  if (n < r)
    return 0;
  ll i, size = modncrlistp.size();
  if (size <= n) {
    modncrlistp.resize(n + 1);
    modncrlistm.resize(n + 1);
    if (!size) {
      modncrlistp[0] = modncrlistm[0] = 1;
      size++;
    }
    For(i, size, n + 1) {
      modncrlistp[i] = modncrlistp[i - 1] * i % mod;
      modncrlistm[i] = modinv(modncrlistp[i]);
    }
  }
  return modncrlistp[n] * modncrlistm[r] % mod * modncrlistm[n - r] % mod;
}

ll modpow(ll a, ll n) {
  ll res = 1;
  while (n > 0) {
    if (n & 1)
      res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}

ll gcd(ll a, ll b) {
  if (!b)
    return abs(a);
  return (a % b == 0) ? abs(b) : gcd(b, a % b);
}
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }

ll countdigits(ll n) {
  ll ans = 0;
  while (n) {
    n /= 10;
    ans++;
  }
  return ans;
}

ll sumdigits(ll n) {
  ll ans = 0;
  while (n) {
    ans += n % 10;
    n /= 10;
  }
  return ans;
}

void topcoder(vector<int> &v) {
  string s;
  while (1) {
    cin >> s;
    int i = s[0] == '{', x = 0;
    while (s[i] >= '0' && s[i] <= '9') {
      x = x * 10 + s[i] - '0';
      ++i;
    }
    v.eb(x);
    if (s[i] == '}')
      break;
  }
}
void topcoder(string &s) {
  string t;
  cin >> t;
  int i = 1;
  while (t[i] != '"') {
    s += t[i++];
  }
}
int main() {
  startupcpp();
  // int codeforces;cin>>codeforces;while(codeforces--){
  ll i, a, b, t, N, cnt = 0, ans = 1, zerof = 0, zeros = 0;
  cin >> N;
  pvec v, ch;
  map<datas, ll> mp;
  rep(i, N) {
    cin >> a >> b;
    if (a == 0 || b == 0) {
      if (a == 0 && b == 0) {
        ++cnt;
      } else if (a == 0) {
        zerof++;
      } else {
        zeros++;
      }
      --N;
      --i;
      continue;
    }
    t = gcd(abs(a), abs(b));
    a /= t;
    b /= t;
    if (b < 0) {
      a *= -1;
      b *= -1;
    }
    v.eb(datas(a, b));
    mp[v[i]]++;
  }
  rep(i, N) {
    swap(v[i].first, v[i].second);
    v[i].first *= -1;
    if (v[i].second < 0) {
      v[i].first *= -1;
      v[i].second *= -1;
    }
    if (mp[v[i]]) {
      t = mp[v[i]];
      mp[v[i]] = 0;
      swap(v[i].first, v[i].second);
      v[i].first *= -1;
      if (v[i].second < 0) {
        v[i].first *= -1;
        v[i].second *= -1;
      }
      ch.eb(mp[v[i]], t);
      mp[v[i]] = 0;
    }
  }
  t = N;
  if (zerof | zeros) {
    if (zerof * zeros == 0)
      t += zerof | zeros;
    else
      (ans *= (modpow(2, zerof) + modpow(2, zeros) - 1) % mod) %= mod;
  }
  for (auto x : ch) {
    (ans *= (modpow(2, x.first) + modpow(2, x.second) - 1) % mod) %= mod;
    t -= x.first + x.second;
  }
  print((ans * modpow(2, t) + mod - 1 + cnt) % mod);
}

Error: 0

Fixed submission:

#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
// #include<ext/pb_ds/assoc_container.hpp>
// #include<ext/pb_ds/tree_policy.hpp>
// #include<ext/pb_ds/tag_and_trait.hpp>
// using namespace __gnu_pbds;
// #include<boost/multiprecision/cpp_int.hpp>
// namespace multiprecisioninteger = boost::multiprecision;
// using cint=multiprecisioninteger::cpp_int;
using namespace std;
using ll = long long;
#define double long double
using datas = pair<ll, ll>;
using ddatas = pair<double, double>;
using tdata = pair<ll, datas>;
using vec = vector<ll>;
using mat = vector<vec>;
using pvec = vector<datas>;
using pmat = vector<pvec>;
// using
// llset=tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>;
#define For(i, a, b) for (i = a; i < (ll)b; ++i)
#define bFor(i, b, a) for (i = b, --i; i >= (ll)a; --i)
#define rep(i, N) For(i, 0, N)
#define rep1(i, N) For(i, 1, N)
#define brep(i, N) bFor(i, N, 0)
#define brep1(i, N) bFor(i, N, 1)
#define all(v) (v).begin(), (v).end()
#define allr(v) (v).rbegin(), (v).rend()
#define vsort(v) sort(all(v))
#define vrsort(v) sort(allr(v))
#define endl "\\n"
#define eb emplace_back
#define print(v) cout << v << endl
#define printyes cout << "Yes" << endl
#define printno cout << "No" << endl
#define printYES cout << "YES" << endl
#define printNO cout << "NO" << endl
#define output(v)                                                              \\
  do {                                                                         \\
    bool f = 0;                                                                \\
    for (auto outi : v) {                                                      \\
      cout << (f ? " " : "") << outi;                                          \\
      f = 1;                                                                   \\
    }                                                                          \\
    cout << endl;                                                              \\
  } while (0)
#define matoutput(v)                                                           \\
  do {                                                                         \\
    for (auto outimat : v)                                                     \\
      output(outimat);                                                         \\
  } while (0)
const ll mod = 1000000007;
// const ll mod=998244353;
const ll inf = 1LL << 60;
const double PI = acos(-1);
const double eps = 1e-9;
template <class T> inline bool chmax(T &a, T b) {
  bool x = a < b;
  if (x)
    a = b;
  return x;
}
template <class T> inline bool chmin(T &a, T b) {
  bool x = a > b;
  if (x)
    a = b;
  return x;
}

void startupcpp() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(15);
}

double distance(ddatas x, ddatas y) {
  double a = x.first - y.first, b = x.second - y.second;
  return sqrt(a * a + b * b);
}

ll modinv(ll a) {
  ll b = mod, u = 1, v = 0, t;
  while (b) {
    t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  return (u + mod) % mod;
}

ll moddevide(ll a, ll b) { return (a * modinv(b)) % mod; }

vec modncrlistp, modncrlistm;

ll modncr(ll n, ll r) {
  if (n < r)
    return 0;
  ll i, size = modncrlistp.size();
  if (size <= n) {
    modncrlistp.resize(n + 1);
    modncrlistm.resize(n + 1);
    if (!size) {
      modncrlistp[0] = modncrlistm[0] = 1;
      size++;
    }
    For(i, size, n + 1) {
      modncrlistp[i] = modncrlistp[i - 1] * i % mod;
      modncrlistm[i] = modinv(modncrlistp[i]);
    }
  }
  return modncrlistp[n] * modncrlistm[r] % mod * modncrlistm[n - r] % mod;
}

ll modpow(ll a, ll n) {
  ll res = 1;
  while (n > 0) {
    if (n & 1)
      res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}

ll gcd(ll a, ll b) {
  if (!b)
    return abs(a);
  return (a % b == 0) ? abs(b) : gcd(b, a % b);
}
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }

ll countdigits(ll n) {
  ll ans = 0;
  while (n) {
    n /= 10;
    ans++;
  }
  return ans;
}

ll sumdigits(ll n) {
  ll ans = 0;
  while (n) {
    ans += n % 10;
    n /= 10;
  }
  return ans;
}

void topcoder(vector<int> &v) {
  string s;
  while (1) {
    cin >> s;
    int i = s[0] == '{', x = 0;
    while (s[i] >= '0' && s[i] <= '9') {
      x = x * 10 + s[i] - '0';
      ++i;
    }
    v.eb(x);
    if (s[i] == '}')
      break;
  }
}
void topcoder(string &s) {
  string t;
  cin >> t;
  int i = 1;
  while (t[i] != '"') {
    s += t[i++];
  }
}
int main() {
  startupcpp();
  // int codeforces;cin>>codeforces;while(codeforces--){
  ll i, t, N, ans = 1;
  cin >> N;
  pvec v(N), ch;
  map<datas, ll> mp;
  rep(i, N) {
    cin >> v[i].first >> v[i].second;
    t = gcd(v[i].first, v[i].second);
    v[i].first /= t;
    v[i].second /= t;
    if (v[i].second < 0) {
      v[i].first *= -1;
      v[i].second *= -1;
    }
    mp[v[i]]++;
  }
  rep(i, N) {
    swap(v[i].first, v[i].second);
    v[i].first *= -1;
    if (v[i].second < 0) {
      v[i].first *= -1;
      v[i].second *= -1;
    }
    if (mp[v[i]]) {
      t = mp[v[i]];
      mp[v[i]] = 0;
      swap(v[i].first, v[i].second);
      v[i].first *= -1;
      if (v[i].second < 0) {
        v[i].first *= -1;
        v[i].second *= -1;
      }
      ch.eb(mp[v[i]], t);
      mp[v[i]] = 0;
    }
  }
  t = N;
  for (auto x : ch) {
    (ans *= (modpow(2, x.first) + modpow(2, x.second) - 1) % mod) %= mod;
    t -= x.first + x.second;
  }
  print((ans * modpow(2, t) + mod - 1) % mod);
}