Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<ll> vi;
#define INF (1e9)
ll MOD = 1000000007;

ll mpow(ll a, ll n) {  // a^n (mod MOD)
    // 二分累乗法 O(log n)
    ll ans = 1;
    while (n != 0) {
        if (n & 1) ans = ans * a % MOD;
        a = a * a % MOD;
        n >>= 1;
    }
    return ans % MOD;
}

int main() {
    ll N, ans = 1;
    cin >> N;
    map<pair<ll, ll>, pair<ll, ll>> m;
    ll a0 = 0, b0 = 0, ab0 = 0;
    for (ll i = 0; i < N; i++) {
        ll a, b;
        cin >> a >> b;
        if (a == 0 && b != 0) {
            a0++;
            continue;
        } else if (b == 0 && a != 0) {
            b0++;
            continue;
        } else if (a == 0 && b == 0) {
            ab0++;
            continue;
        }
        if (b < 0) {
            a *= -1;
            b *= -1;
        }
        ll g = gcd(a, b);
        a /= g;
        b /= g;
        m[make_pair(a, b)]++;
    }

    ans *= (mpow(2, a0) + mpow(2, b0) + MOD - 1) % MOD;
    ans %= MOD;

    for (auto& [key, value] : m) {
        if (value == 0) continue;
        ll a = key.first, b = key.second;
        ll c = 1;
        if (a < 0) c *= -1;
        auto x = m[make_pair(b * c * -1, a * c)];
        if (-a == b) {
            ans *= value + 1 + x;
            ans %= MOD;
            if (x > 0)
                m[make_pair(b * c * -1, a * c)] = 0;
        } else if (x == 0) {
            ans *= mpow(2, value);
            ans %= MOD;
        } else {
            ans *= (mpow(2, value) + mpow(2, x) + MOD - 1) % MOD;
            ans %= MOD;
            if (x > 0)
                m[make_pair(b * c * -1, a * c)] = 0;
        }
        // cout << ' ' << key.first << ' ' << key.second << ' ' << value << "   " << -b * c << ' ' << a * c << ' ' << x << "   " << ans << endl;
        m[key] = 0;
    }

    ans += ab0;
    ans += MOD - 1;
    ans %= MOD;

    cout << ans << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:45:27: error: no 'operator++(int)' declared for postfix '++' [-fpermissive]
   45 |         m[make_pair(a, b)]++;
a.cc:52:19: error: no match for 'operator==' (operand types are 'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} and 'int')
   52 |         if (value == 0) continue;
      |             ~~~~~ ^~ ~
      |             |        |
      |             |        int
      |             std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type {aka std::pair<long long int, long long int>}
In file included from /usr/include/c++/14/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:181,
                 from a.cc:1:
/usr/include/c++/14/bits/regex.h:1103:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator==(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1103 |     operator==(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1103:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:1199:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator==(__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const sub_match<_BiIter>&)'
 1199 |     operator==(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1199:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:1274:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator==(const sub_match<_BiIter>&, __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)'
 1274 |     operator==(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1274:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:1366:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1366 |     operator==(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1366:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:1441:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1441 |     operator==(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1441:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:1534:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1534 |     operator==(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1534:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:1613:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1613 |     operator==(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1613:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/regex.h:2186:5: note: candidate: 'template<class _Bi_iter, class _Alloc> bool std::__cxx11::operator==(const match_results<_BiIter, _Alloc>&, const match_results<_BiIter, _Alloc>&)'
 2186 |     operator==(const match_results<_Bi_iter, _Alloc>& __m1,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:2186:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::__cxx11::match_results<_BiIter, _Alloc>'
   52 |         if (value == 0) continue;
      |                      ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_pair.h:1033:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator==(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1033 |     operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1033:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   mismatched types 'const std::pair<_T1, _T2>' and 'int'
   52 |         if (value == 0) continue;
      |                      ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:441:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator==(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  441 |     operator==(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:441:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::reverse_iterator<_Iterator>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/stl_iterator.h:486:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator==(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  486 |     operator==(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:486:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::reverse_iterator<_Iterator>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/stl_iterator.h:1667:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator==(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1667 |     operator==(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1667:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::move_iterator<_IteratorL>'
   52 |         if (value == 0) continue;
      |                      ^
/usr/include/c++/14/bits/stl_iterator.h:1737:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator==(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1737 |     operator==(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1737:5: note:   template argument deduction/substitution failed:
a.cc:52:22: note:   'std::tuple_element<1, std::pair<const std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::type' {aka 'std::pair<long long int, long long int>'} is not derived from 'const std::move_iterator<_IteratorL>'
   52 |         if (value == 0) continue;
      |                      ^
In file included from /usr/include/c++/14/bits/char_traits.h:42,
                 from /usr/include/c++/14/string:42,
                 from /