Language: C++

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

int main() {
  map<string, int> v(2);
  string a,b,c;
  cin >> a, b;
  cin >> v[a] >> v[b];
  cin >> c;
  v[c]--;
  cout >> v[a] >> " " >> v[b] >> endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:5:23: error: no matching function for call to 'std::map<std::__cxx11::basic_string<char>, int>::map(int)'
    5 |   map<string, int> v(2);
      |                       ^
In file included from /usr/include/c++/14/map:63,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:152,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_map.h:302:9: note: candidate: 'template<class _InputIterator> std::map<_Key, _Tp, _Compare, _Alloc>::map(_InputIterator, _InputIterator, const _Compare&, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  302 |         map(_InputIterator __first, _InputIterator __last,
      |         ^~~
/usr/include/c++/14/bits/stl_map.h:302:9: note:   candidate expects 3 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:285:9: note: candidate: 'template<class _InputIterator> std::map<_Key, _Tp, _Compare, _Alloc>::map(_InputIterator, _InputIterator) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  285 |         map(_InputIterator __first, _InputIterator __last)
      |         ^~~
/usr/include/c++/14/bits/stl_map.h:285:9: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:268:9: note: candidate: 'template<class _InputIterator> std::map<_Key, _Tp, _Compare, _Alloc>::map(_InputIterator, _InputIterator, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  268 |         map(_InputIterator __first, _InputIterator __last,
      |         ^~~
/usr/include/c++/14/bits/stl_map.h:268:9: note:   candidate expects 3 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:262:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::initializer_list<std::pair<const _Key, _Val> >, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  262 |       map(initializer_list<value_type> __l, const allocator_type& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:262:7: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:256:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::map<_Key, _Tp, _Compare, _Alloc>&&, std::__type_identity_t<_Alloc>&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; std::__type_identity_t<_Alloc> = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  256 |       map(map&& __m, const __type_identity_t<allocator_type>& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:256:7: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:252:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const std::map<_Key, _Tp, _Compare, _Alloc>&, std::__type_identity_t<_Alloc>&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; std::__type_identity_t<_Alloc> = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  252 |       map(const map& __m, const __type_identity_t<allocator_type>& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:252:7: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:248:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  248 |       map(const allocator_type& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:248:33: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, int>::allocator_type&' {aka 'const std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >&'}
  248 |       map(const allocator_type& __a)
      |           ~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:240:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::initializer_list<std::pair<const _Key, _Val> >, const _Compare&, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  240 |       map(initializer_list<value_type> __l,
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:240:40: note:   no known conversion for argument 1 from 'int' to 'std::initializer_list<std::pair<const std::__cxx11::basic_string<char>, int> >'
  240 |       map(initializer_list<value_type> __l,
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:227:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::map<_Key, _Tp, _Compare, _Alloc>&&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  227 |       map(map&&) = default;
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:227:11: note:   no known conversion for argument 1 from 'int' to 'std::map<std::__cxx11::basic_string<char>, int>&&'
  227 |       map(map&&) = default;
      |           ^~~~~
/usr/include/c++/14/bits/stl_map.h:219:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const std::map<_Key, _Tp, _Compare, _Alloc>&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  219 |       map(const map&) = default;
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:219:11: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, int>&'
  219 |       map(const map&) = default;
      |           ^~~~~~~~~~
/usr/include/c++/14/bits/stl_map.h:206:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const _Compare&, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  206 |       map(const _Compare& __comp,
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:206:27: note:   no known conversion for argument 1 from 'int' to 'const std::less<std::__cxx11::basic_string<char> >&'
  206 |       map(const _Compare& __comp,
      |           ~~~~~~~~~~~~~~~~^~~~~~
/usr/include/c++/14/bits/stl_map.h:197:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map() [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  197 |       map() = default;
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:197:7: note:   candidate expects 0 arguments, 1 provided
a.cc:11:8: error: no match for 'operator>>' (operand types are 'std::ostream' {aka 'std::basic_ostream<char>'} and 'std::map<std::__cxx11::basic_string<char>, int>::mapped_type' {aka 'int'})
   11 |   cout >> v[a] >> " " >> v[b] >> endl;
a.cc:11:8: note: candidate: 'operator>>(int, std::map<std::__cxx11::basic_string<char>, int>::mapped_type {aka int})' (built-in)
a.cc:11:8: note:   no known conversion for argument 1 from 'std::ostream' {aka 'std::basic_ostream<char>'} to 'int'
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:41:
/usr/include/c++/14/cstddef:131:5: note: candidate: 'template<class _IntegerType> constexpr std::__byte_op_t<_IntegerType> std::operator>>(byte, _IntegerType)'
  131 |     operator>>(byte __b, _IntegerType __shift) noexcept
      |     ^~~~~~~~
/usr/include/c++/14/cstddef:131:5: note:   template argument deduction/substitution failed:
a.cc:11:3: note:   cannot convert 'std::cout' (type 'std::ostream' {aka 'std::basic_ostream<char>'}) to type 'std::byte'
   11 |   cout >> v[a] >> " " >> v[b] >> endl;
      |   ^~~~
In file included from /usr/include/c++/14/string:55,
                 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/basic_string.tcc:835:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::basic_istream<_CharT, _Traits>& std::operator>>(basic_istream<_CharT, _Traits>&, __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
  835 |     operator>>(basic_istream<_CharT, _Traits>& __in,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.tcc:835:5: note:   template argument deduction/substitution failed:
a.cc:11:14: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<_CharT, _Traits>'
   11 |   cout >> v[a] >> " " >> v[b] >> endl;
      |              ^
/usr/include/c++/14/bitset:1597:5: note: candidate: 'template<class _CharT, class _Traits, long unsigned int _Nb> std::basic_istream<_CharT, _Traits>& std::operator>>(basic_istream<_CharT, _Traits>&, bi