Language: C++

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

int variation(string s)
{
  char tmp = s[0];
  int r = 1;
  for(int i = 1; i < s.size(); ++i)
  {
    if(tmp != s[i])
    {
      ++r;
      tmp = s[i];
    }
  }
  return r;
}

int main()
{
  string s;
  cin >> s;
  
  int ans = 0;
  for(int i = 1; i < s.size(); ++i)
  {
    string x = s.substr(0, i), y = s.substr(i);
    ans = max(ans, min(variation(x), variation(y));
  }
  
  cout << ans << endl;
}

Compiler output:
a.cc:2:7: error: expected nested-name-specifier before 'namespce'
    2 | using namespce std;
      |       ^~~~~~~~
a.cc:4:15: error: 'string' was not declared in this scope
    4 | int variation(string s)
      |               ^~~~~~
a.cc:4:15: note: suggested alternatives:
In file included from /usr/include/c++/14/string:41,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52,
                 from a.cc:1:
/usr/include/c++/14/bits/stringfwd.h:77:33: note:   'std::string'
   77 |   typedef basic_string<char>    string;
      |                                 ^~~~~~
/usr/include/c++/14/string:76:11: note:   'std::pmr::string'
   76 |     using string    = basic_string<char>;
      |           ^~~~~~
a.cc: In function 'int main()':
a.cc:21:3: error: 'string' was not declared in this scope
   21 |   string s;
      |   ^~~~~~
a.cc:21:3: note: suggested alternatives:
/usr/include/c++/14/bits/stringfwd.h:77:33: note:   'std::string'
   77 |   typedef basic_string<char>    string;
      |                                 ^~~~~~
/usr/include/c++/14/string:76:11: note:   'std::pmr::string'
   76 |     using string    = basic_string<char>;
      |           ^~~~~~
a.cc:22:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
   22 |   cin >> s;
      |   ^~~
      |   std::cin
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:146:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:22:10: error: 's' was not declared in this scope
   22 |   cin >> s;
      |          ^
a.cc:27:11: error: expected ';' before 'x'
   27 |     string x = s.substr(0, i), y = s.substr(i);
      |           ^~
      |           ;
a.cc:28:34: error: 'x' was not declared in this scope
   28 |     ans = max(ans, min(variation(x), variation(y));
      |                                  ^
a.cc:28:35: error: 'variation' cannot be used as a function
   28 |     ans = max(ans, min(variation(x), variation(y));
      |                                   ^
a.cc:28:48: error: 'y' was not declared in this scope
   28 |     ans = max(ans, min(variation(x), variation(y));
      |                                                ^
a.cc:28:49: error: 'variation' cannot be used as a function
   28 |     ans = max(ans, min(variation(x), variation(y));
      |                                                 ^
a.cc:28:20: error: 'min' was not declared in this scope; did you mean 'std::min'?
   28 |     ans = max(ans, min(variation(x), variation(y));
      |                    ^~~
      |                    std::min
In file included from /usr/include/c++/14/algorithm:61,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_algo.h:5696:5: note: 'std::min' declared here
 5696 |     min(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
a.cc:31:3: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   31 |   cout << ans << endl;
      |   ^~~~
      |   std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:31:18: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   31 |   cout << ans << endl;
      |                  ^~~~
      |                  std::endl
In file included from /usr/include/c++/14/istream:41,
                 from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~