Language: C++

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

using usize = ::std::size_t;
using u64 = ::std::int_least64_t;
//using u64 = long long;
static constexpr u64 Inf = ::std::numeric_limits<u64>::max() / 2;


int main(int argc, char *argv[])
{
    
 
    cin.tie(0);
    ios::sync_with_stdio(false);
    
    u64 X, K, D;
    cin >> X >> K >> D;
    
    if (abs(X)/D > K) {
        cout << X >= 0 ? X - K * D : X + K * D << endl;
    } else {
        if ((abs(X)/D - K)%2 != 0) {
            u64 opt = X >= 0 ? X - (abs(X)/D)*D : X + (abs(X)/D)*D;
            u64 min_value = abs(opt + D);
            for (int i = -1; i <= 1; i += 2) {
                min_value = min(min_value, abs(opt + i * D));
            }
            cout << min_value << endl;
        } else {
            u64 opt = X >= 0 ? X - (abs(X)/D)*D : X + (abs(X)/D)*D;
            u64 min_value = abs(opt);
            for (int i = -2; i <= 2; i += 2) {
                min_value = min(min_value, abs(opt + i * D));
            }
            cout << min_value << endl;
        }
    }
    
    return 0;
}


Compiler output:
a.cc: In function 'int main(int, char**)':
a.cc:22:19: error: no match for 'operator>=' (operand types are 'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} and 'int')
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |         ~~~~~~~~~ ^~ ~
      |              |       |
      |              |       int
      |              std::basic_ostream<char>::__ostream_type {aka std::basic_ostream<char>}
a.cc:22:19: note: candidate: 'operator>=(int, int)' (built-in)
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |         ~~~~~~~~~~^~~~
a.cc:22:19: note:   no known conversion for argument 1 from 'std::basic_ostream<char>::__ostream_type' {aka '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:1165:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1165 |     operator>=(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1165:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/regex.h:1248:5: 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>&)'
 1248 |     operator>=(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1248:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/regex.h:1341:5: 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>&)'
 1341 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1341:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/regex.h:1415:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1415 |     operator>=(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1415:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/regex.h:1509:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1509 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1509:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/regex.h:1586:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1586 |     operator>=(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1586:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/regex.h:1686:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>=(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1686 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1686:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << 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:1070:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator>=(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1070 |     operator>=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1070:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::pair<_T1, _T2>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:476:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>=(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  476 |     operator>=(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:476:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::reverse_iterator<_Iterator>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/stl_iterator.h:520:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>=(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  520 |     operator>=(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:520:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::reverse_iterator<_Iterator>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/stl_iterator.h:1724:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>=(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1724 |     operator>=(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1724:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::move_iterator<_IteratorL>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/bits/stl_iterator.h:1781:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>=(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1781 |     operator>=(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1781:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::move_iterator<_IteratorL>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << 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:739:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator>=(basic_string_view<_CharT, _Traits>, basic_string_view<_CharT, _Traits>)'
  739 |     operator>=(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:739:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/string_view:746:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator>=(basic_string_view<_CharT, _Traits>, __type_identity_t<basic_string_view<_CharT, _Traits> >)'
  746 |     operator>=(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:746:5: note:   template argument deduction/substitution failed:
a.cc:22:22: note:   'std::basic_ostream<char>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   22 |         cout << X >= 0 ? X - K * D : X + K * D << endl;
      |                      ^
/usr/include/c++/14/string_