Language: C++

#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#define FAST ;
#else
#define FAST ios::sync_with_stdio(0);cin.tie(0);
#define endl '\n'
#endif
#define _ <<' '<<
#define Fr(i, s, e) for(auto i = s; i < e; ++i)
#define Ft first
#define Sd second
using ll = long long;
using pii = pair<int, int>;
constexpr ll MAX = 1e6+5;
constexpr ll INF = 2134567890;
constexpr ll MOD = 998244353;

ll fpow(ll b, ll a, ll MOD = MOD) {
    b %= MOD;
    ll r = 1;
    for(; a; b=b*b%MOD, a>>=1)
        a&1 && (r = r*b%MOD);
    return r;
}

signed main() {
    FAST;

    string N;
    int K;
    cin >> N >> K;
    const auto FC = [](int N, int M) {
        if (N > M) return 0;
        //assert(0 <= N && N <= M);
        int rt = 1;
        int ed = min(N, M-N);
        Fr(i, 0, ed) rt = rt*(M-i)/(i+1);
        return rt*int(fpow(9,N));
    };
    function<int(string, int)> solve;
    solve = [&](string N, int K) {
        if (N.empty() || !K) return 1;
        if (N[0] == '0') return solve(N.substr(1), K);
        //cerr _ N[0]-'0'-1 _ N.size() _ K _ FC(K-1,N.size()-1) _ FC(K,N.size()-1) _ endl;
        return solve(N.substr(1), K-1) + (N[0]-'0'-1)*FC(K-1,N.size()-1) + FC(K,N.size()-1);
    };
    int cnt = 0;
    for(char c: N) cnt += c!='0';
    cout << solve(N, K)+cnt>K << endl;

}


Compiler output:
a.cc: In function 'int main()':
a.cc:51:28: error: no match for 'operator>' (operand types are 'std::basic_ostream<char>' and 'int')
   51 |     cout << solve(N, K)+cnt>K << endl;
      |     ~~~~~~~~~~~~~~~~~~~~~~~^
      |          |
      |          std::basic_ostream<char>
a.cc:51:28: note: candidate: 'operator>(int, int)' (built-in)
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                            ^
a.cc:51:28: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to '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:1176:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator>(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1176 |     operator>(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1176:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/regex.h:1236:5: 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>&)'
 1236 |     operator>(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1236:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/regex.h:1329:5: 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>&)'
 1329 |     operator>(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1329:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/regex.h:1403:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1403 |     operator>(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1403:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/regex.h:1497:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1497 |     operator>(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1497:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/regex.h:1573:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1573 |     operator>(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1573:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/regex.h:1673:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1673 |     operator>(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1673:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
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:1058:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator>(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1058 |     operator>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1058:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::pair<_T1, _T2>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:462:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  462 |     operator>(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:462:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::reverse_iterator<_Iterator>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/stl_iterator.h:507:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  507 |     operator>(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:507:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::reverse_iterator<_Iterator>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/stl_iterator.h:1714:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1714 |     operator>(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1714:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::move_iterator<_IteratorL>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/bits/stl_iterator.h:1774:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1774 |     operator>(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1774:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'const std::move_iterator<_IteratorL>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/string_view:695:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator>(basic_string_view<_CharT, _Traits>, basic_string_view<_CharT, _Traits>)'
  695 |     operator> (basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:695:5: note:   template argument deduction/substitution failed:
a.cc:8:14: note:   'std::basic_ostream<char>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
    8 | #define endl '\n'
      |              ^~~~
a.cc:51:34: note: in expansion of macro 'endl'
   51 |     cout << solve(N, K)+cnt>K << endl;
      |                                  ^~~~
/usr/include/c++/14/string_view:702:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator>(b