func_code_string: #include <bits/stdc++.h>   using namespace std;   template <typename T, typename A>   istream& operator>>(istream& in, vector<T, A>& p) {     for (auto& i : p) in >> i;     return in;   }   template <typename T, typename A>   ostream& operator<<(ostream& out, std::vector<T, A> const& v) {     for (auto i : v) out << i <<    ;     return out;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n, m, a, b;     cin >> n >> m;     vector<int> cnt(n);     int ans = n;     for (int i = 0; i < m; ++i) {       cin >> a >> b;       --a, --b;       if (a > b) swap(a, b);       if (cnt[a] == 0) ans--;       cnt[a]++;     }     int q, t;     cin >> q;     for (int i = 0; i < q; ++i) {       cin >> t;       if (t == 1) {         cin >> a >> b;         --a, --b;         if (a > b) swap(a, b);         if (cnt[a] == 0) ans--;         cnt[a]++;       } else if (t == 2) {         cin >> a >> b;         --a, --b;         if (a > b) swap(a, b);         if (cnt[a] == 1) ans++;         cnt[a]--;       } else         cout << ans <<   n ;     }   }   