Language: C++

#include <bits/stdc++.h>
#define INF 100000000000
#define ll long long
#define pll pair<ll, ll>
using namespace std;

int main()
{
  ll N, K;
  cin >> N >> K;
  string S;
  cin >> S;
  vector<pair<char, ll>> char_list;
  char now;
  ll cnt = 1;
  for (ll i = 0; i < N; ++i) {
    if (i == 0) {
      now = S[i];
      continue;
    }
    if (now == S[i]) {
      cnt += 1;
    }
    else {
      char_list.push_back({now, cnt});
      now = S[i];
      cnt = 1;
    }
  }
  char_list.push_back({now, cnt});
  ll ans = 0;
  for (ll i = 0; i < char_list.size(); ++i) {
    ans += char_list.at(i).second - 1;
  }
  ll r_cnt = 0, l_cnt = 0;
  for (ll i = 1; i < char_list.size() - 1; ++i) {
    if (char_list.at(i).first == 'L') {
      l_cnt += 1;
    }
    else {
      r_cnt += 1;
    }
  }
  char check;
  if (r_cnt > l_cnt) {
    check = 'R';
  }
  else {
    check = 'L';
  }
  if (max(r_cnt, l_cnt) >= K) {
    ans += 2 * K;
    cout << ans << endl;
    return 0;
  }
  else {
    ans += 2 * max(r_cnt, l_cnt);
    if (char_list.at(0).first != check) {
      ans += 1;
    }
    if (char_list.at(char_list.size() - 1).first != check) {
      ans += 1;
    }
    cout << ans << endl;
    cout << char_list.at(char_list.size()) << endl;
  }
}


Compiler output:
a.cc: In function 'int main()':
a.cc:65:10: error: no match for 'operator<<' (operand types are 'std::ostream' {aka 'std::basic_ostream<char>'} and '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'})
   65 |     cout << char_list.at(char_list.size()) << endl;
      |     ~~~~ ^~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |     |                   |
      |     |                   __gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type {aka std::pair<char, long long int>}
      |     std::ostream {aka std::basic_ostream<char>}
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,
                 from a.cc:1:
/usr/include/c++/14/ostream:116:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(__ostream_type& (*)(__ostream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  116 |       operator<<(__ostream_type& (*__pf)(__ostream_type&))
      |       ^~~~~~~~
/usr/include/c++/14/ostream:116:36: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'std::basic_ostream<char>::__ostream_type& (*)(std::basic_ostream<char>::__ostream_type&)' {aka 'std::basic_ostream<char>& (*)(std::basic_ostream<char>&)'}
  116 |       operator<<(__ostream_type& (*__pf)(__ostream_type&))
      |                  ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/ostream:125:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>; __ios_type = std::basic_ios<char>]'
  125 |       operator<<(__ios_type& (*__pf)(__ios_type&))
      |       ^~~~~~~~
/usr/include/c++/14/ostream:125:32: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'std::basic_ostream<char>::__ios_type& (*)(std::basic_ostream<char>::__ios_type&)' {aka 'std::basic_ios<char>& (*)(std::basic_ios<char>&)'}
  125 |       operator<<(__ios_type& (*__pf)(__ios_type&))
      |                  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
/usr/include/c++/14/ostream:135:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  135 |       operator<<(ios_base& (*__pf) (ios_base&))
      |       ^~~~~~~~
/usr/include/c++/14/ostream:135:30: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'std::ios_base& (*)(std::ios_base&)'
  135 |       operator<<(ios_base& (*__pf) (ios_base&))
      |                  ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
/usr/include/c++/14/ostream:174:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  174 |       operator<<(long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:174:23: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'long int'
  174 |       operator<<(long __n)
      |                  ~~~~~^~~
/usr/include/c++/14/ostream:178:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  178 |       operator<<(unsigned long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:178:32: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'long unsigned int'
  178 |       operator<<(unsigned long __n)
      |                  ~~~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:182:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(bool) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  182 |       operator<<(bool __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:182:23: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'bool'
  182 |       operator<<(bool __n)
      |                  ~~~~~^~~
In file included from /usr/include/c++/14/ostream:1022:
/usr/include/c++/14/bits/ostream.tcc:96:5: note: candidate: 'std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(short int) [with _CharT = char; _Traits = std::char_traits<char>]'
   96 |     basic_ostream<_CharT, _Traits>::
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/ostream.tcc:97:22: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'short int'
   97 |     operator<<(short __n)
      |                ~~~~~~^~~
/usr/include/c++/14/ostream:189:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(short unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  189 |       operator<<(unsigned short __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:189:33: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'short unsigned int'
  189 |       operator<<(unsigned short __n)
      |                  ~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/ostream.tcc:110:5: note: candidate: 'std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(int) [with _CharT = char; _Traits = std::char_traits<char>]'
  110 |     basic_ostream<_CharT, _Traits>::
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/ostream.tcc:111:20: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'int'
  111 |     operator<<(int __n)
      |                ~~~~^~~
/usr/include/c++/14/ostream:200:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  200 |       operator<<(unsigned int __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:200:31: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'unsigned int'
  200 |       operator<<(unsigned int __n)
      |                  ~~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:211:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  211 |       operator<<(long long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:211:28: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'long long int'
  211 |       operator<<(long long __n)
      |                  ~~~~~~~~~~^~~
/usr/include/c++/14/ostream:215:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  215 |       operator<<(unsigned long long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:215:37: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long int>'} to 'long long unsigned int'
  215 |       operator<<(unsigned long long __n)
      |                  ~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:231:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(double) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  231 |       operator<<(double __f)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:231:25: note:   no known conversion for argument 1 from '__gnu_cxx::__alloc_traits<std::allocator<std::pair<char, long long int> >, std::pair<char, long long int> >::value_type' {aka 'std::pair<char, long long