Language: C++

#include<bits/stdc++.h>
using namespace std;
using ll=long long;
using Graph=vector<vector<int>>;
using P=pair<int,int>;

int n,m,k,i,j;
vector<int> cc_id;//どの連結成分か
vector<int> cc_num;//連結成分のsize


void dfs(Graph &G,int v,int &cnt){
    cc_id=id;//vスタートの連結成分は全てidにしておく
    cnt++;//連結成分の個数
    for(auto next:G[v]){//vを親としてdfsを続ける
        if(cc_id==-1){//訪れていなければ
            dfs(G,next,cnt);
        }
    }
}

int main(){
    int n,m,k;
    cin>>n>>m>>k;
    Graph G(n);
    vector<int> a(m),b(m);
    for(i=0;i<m;i++){
        cin>>a[i]>>b[i];
        a[i]--;b[i]--;
        G[a].push_back({b});
        G[b].push_back({a});        
    }
    vector<int> c(k),d(k);
    for(i=0;i<k;i++){
        cin>>c[i]>>d[i];
        c[i]--;d[i]--;
    }

    int id=0;
    cc_id.assign(n,-1);//-1ならまだ訪れていない
    for(i=0;i<n;i++){
        if(cc_id==-1){//訪れていないとき    
            int cnt=0;
            dfs(G,i,cnt);//sizeを調べる
            id++;//同じ連結成分ならおなじid
            cc_num.push_back(cnt);//size
        }
    }

    vector<int> ans(n,0);
    for(i=0;i<n;i++){ans[i]=cc_num[i]-1-(int)G[i].size();}//自分と自分の周り(友達)をのぞく
    for(i=0;i<n;i++){
        if(cc_id[c[i]]==cc_id[d[i]]){//同じ連結成分にブロック関係があったら除く
            ans[c[i]]--;
            ans[d[i]]--;
        }
    }

    for(i=0;i<n;i++){
        cout<<ans[i]<<" ";
    }
    cout<<endl;
    return 0;
}

Compiler output:
a.cc: In function 'void dfs(Graph&, int, int&)':
a.cc:13:11: error: 'id' was not declared in this scope; did you mean 'i'?
   13 |     cc_id=id;//vスタートの連結成分は全てidにしておく
      |           ^~
      |           i
a.cc:16:17: error: no match for 'operator==' (operand types are 'std::vector<int>' and 'int')
   16 |         if(cc_id==-1){//訪れていなければ
      |            ~~~~~^~~~
      |            |      |
      |            |      int
      |            std::vector<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:16:20: note:   'std::vector<int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::__cxx11::match_results<_BiIter, _Alloc>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
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:16:20: note:   'std::vector<int>' is not derived from 'const std::pair<_T1, _T2>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
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:16:20: note:   'std::vector<int>' is not derived from 'const std::reverse_iterator<_Iterator>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::reverse_iterator<_Iterator>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::move_iterator<_IteratorL>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
/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:16:20: note:   'std::vector<int>' is not derived from 'const std::move_iterator<_IteratorL>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
In file included from /usr/include/c++/14/bits/char_traits.h:42,
                 from /usr/include/c++/14/string:42,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/bits/postypes.h:192:5: note: candidate: 'template<class _StateT> bool std::operator==(const fpos<_StateT>&, const fpos<_StateT>&)'
  192 |     operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/postypes.h:192:5: note:   template argument deduction/substitution failed:
a.cc:16:20: note:   'std::vector<int>' is not derived from 'const std::fpos<_StateT>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
In file included from /usr/include/c++/14/string:43:
/usr/include/c++/14/bits/allocator.h:235:5: note: candidate: 'template<class _T1, class _T2> bool std::operator==(const allocator<_CharT>&, const allocator<_T2>&)'
  235 |     operator==(const allocator<_T1>&, const allocator<_T2>&)
      |     ^~~~~~~~
/usr/include/c++/14/bits/allocator.h:235:5: note:   template argument deduction/substitution failed:
a.cc:16:20: note:   'std::vector<int>' is not derived from 'const std::allocator<_CharT>'
   16 |         if(cc_id==-1){//訪れていなければ
      |                    ^
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54:
/usr/include/c++/14/string_view:629:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator==(basic_string_view<_CharT, _Traits>, __type_identity_t<basic_string_view<_CharT, _Traits> >)'
  629 |     operator==(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr