Language: C++

#include <iostream>
#include <map>
#include <string>
using namespace std;

int main() {
	int s = 0;
	int n = 1000000;

	cin >> s;

	map<int, int> list;
	list.insert((pair<int, string>(s, 1)));

	int m = 0;
	for (int i = 1; i < n; i++) {
		if (i % 2 == 0) {
			m = i / 2;

		} else {
			m = 3 * i + 1;
		}
		cout << m << " ";
		map<int, string>::iterator it;
		it = list.find(m);
		if (it == list.end()) {
			list.insert((pair<int, string>(m, i+1)));
		} else {
			cout << i + 1 << endl;
			break;
		}

	}

	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:13:44: error: no matching function for call to 'std::pair<int, std::__cxx11::basic_string<char> >::pair(int&, int)'
   13 |         list.insert((pair<int, string>(s, 1)));
      |                                            ^
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/string:51,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_pair.h:913:28: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(std::_PCC<((! std::is_same<int, _U1>::value) || (! std::is_same<std::__cxx11::basic_string<char>, _U2>::value)), int, std::__cxx11::basic_string<char> >::_MoveConstructiblePair<_U1, _U2>() && (! std::_PCC<((! std::is_same<int, _U1>::value) || (! std::is_same<std::__cxx11::basic_string<char>, _U2>::value)), int, std::__cxx11::basic_string<char> >::_ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(std::pair<_U1, _U2>&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && (! std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> = _U2; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  913 |         explicit constexpr pair(pair<_U1, _U2>&& __p)
      |                            ^~~~
/usr/include/c++/14/bits/stl_pair.h:913:28: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_pair.h:902:19: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(std::_PCC<((! std::is_same<int, _U1>::value) || (! std::is_same<std::__cxx11::basic_string<char>, _U2>::value)), int, std::__cxx11::basic_string<char> >::_MoveConstructiblePair<_U1, _U2>() && std::_PCC<((! std::is_same<int, _U1>::value) || (! std::is_same<std::__cxx11::basic_string<char>, _U2>::value)), int, std::__cxx11::basic_string<char> >::_ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(std::pair<_U1, _U2>&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> = _U2; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  902 |         constexpr pair(pair<_U1, _U2>&& __p)
      |                   ^~~~
/usr/include/c++/14/bits/stl_pair.h:902:19: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_pair.h:891:28: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(_MoveConstructiblePair<_U1, _U2>() && (! _ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, _U2&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<true, _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && (! std::_PCC<true, _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> = _U2; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  891 |         explicit constexpr pair(_U1&& __x, _U2&& __y)
      |                            ^~~~
/usr/include/c++/14/bits/stl_pair.h:891:28: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:890:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  890 |                          bool>::type=false>
      |                                      ^~~~~
/usr/include/c++/14/bits/stl_pair.h:881:19: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(_MoveConstructiblePair<_U1, _U2>() && _ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, _U2&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<true, _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && std::_PCC<true, _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> = _U2; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  881 |         constexpr pair(_U1&& __x, _U2&& __y)
      |                   ^~~~
/usr/include/c++/14/bits/stl_pair.h:881:19: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:880:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  880 |                          bool>::type=true>
      |                                      ^~~~
/usr/include/c++/14/bits/stl_pair.h:869:9: note: candidate: 'template<class _U2, typename std::enable_if<std::__and_<std::is_pointer<int>, std::__not_<std::is_reference<_Tp> >, std::is_constructible<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, _U2>, std::__not_<std::is_constructible<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, const _U1&> >, std::__not_<std::is_convertible<_U2, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(__zero_as_null_pointer_constant, _U2&&, ...) [with typename std::enable_if<std::__and_<std::is_pointer<_Tp>, std::__not_<std::is_reference<_U1> >, std::is_constructible<_T2, _U2>, std::__not_<std::is_constructible<_T1, const _U1&> >, std::__not_<std::is_convertible<_U2, _T2> > >::value, bool>::type <anonymous> = _U2; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  869 |         pair(__zero_as_null_pointer_constant, _U2&& __y, ...)
      |         ^~~~
/usr/include/c++/14/bits/stl_pair.h:869:9: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:866:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  866 |                              bool> = false>
      |                                      ^~~~~
/usr/include/c++/14/bits/stl_pair.h:856:9: note: candidate: 'template<class _U2, typename std::enable_if<std::__and_<std::is_pointer<int>, std::__not_<std::is_reference<_Tp> >, std::is_constructible<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, _U2>, std::__not_<std::is_constructible<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, const _U1&> >, std::is_convertible<_U2, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(__zero_as_null_pointer_constant, _U2&&, ...) [with typename std::enable_if<std::__and_<std::is_pointer<_Tp>, std::__not_<std::is_reference<_U1> >, std::is_constructible<_T2, _U2>, std::__not_<std::is_constructible<_T1, const _U1&> >, std::is_convertible<_U2, _T2> >::value, bool>::type <anonymous> = _U2; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  856 |         pair(__zero_as_null_pointer_constant, _U2&& __y, ...)
      |         ^~~~
/usr/include/c++/14/bits/stl_pair.h:856:9: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:853:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  853 |                              bool> = true>
      |                                      ^~~~
/usr/include/c++/14/bits/stl_pair.h:843:9: note: candidate: 'template<class _U1, typename std::enable_if<std::__and_<std::__not_<std::is_reference<_Tp> >, std::is_pointer<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::is_constructible<int, _U1>, std::__not_<std::is_constructible<int, const _U1&> >, std::__not_<std::is_convertible<_Iter, int> > >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, __zero_as_null_pointer_constant, ...) [with typename std::enable_if<std::__and_<std::__not_<std::is_reference<_U1> >, std::is_pointer<_T2>, std::is_constructible<_T1, _U1>, std::__not_<std::is_constructible<_T1, const _U1&> >, std::__not_<std::is_convertible<_Iter, _Iterator> > >::value, bool>::type <anonymous> = _U1; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  843 |         pair(_U1&& __x, __zero_as_null_pointer_constant, ...)
      |         ^~~~
/usr/include/c++/14/bits/stl_pair.h:843:9: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:840:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  840 |                              bool> = false>
      |                                      ^~~~~
/usr/include/c++/14/bits/stl_pair.h:830:9: note: candidate: 'template<class _U1, typename std::enable_if<std::__and_<std::__not_<std::is_reference<_Tp> >, std::is_pointer<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::is_constructible<int, _U1>, std::__not_<std::is_constructible<int, const _U1&> >, std::is_convertible<_Iter, int> >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, __zero_as_null_pointer_constant, ...) [with typename std::enable_if<std::__and_<std::__not_<std::is_reference<_U1> >, std::is_pointer<_T2>, std::is_constructible<_T1, _U1>, std::__not_<std::is_constructible<_T1, const _U1&> >, std::is_convertible<_Iter, _Iterator> >::value, bool>::type <anonymous> = _U1; _T1 = int; _T2 = std::__cxx11::basic_string<char>]'
  830 |         pair(_U1&& __x, __zero_as_null_pointer_constant, ...)
      |         ^~~~
/usr/include/c++/14/bits/stl_pair.h:830:9: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:827:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  827 |                              bool> = true>
      |                                      ^~~~
/usr/include/c++/14/bits/stl_pair.h:789:28: note: candidate: 'template<clas