Language: C++

#include <iostream>
#include <string>
#include <vector>
#include <list>
#include <map>
#include <queue>
#include <stack>
#include <algorithm>
#include <fstream>
#include <sstream>
#include <iomanip>

using namespace std;

long long MOD = 1000000007;

int main(){
    string S;
    cin >> S;
    map<string, string> mp;
    mp['Sunny']='Cloudy';
    mp['Cloudy']='Rainy';
    mp['Rainy']='Sunny';

    cout << mp[S] << endl;
}

Compiler output:
a.cc:21:8: warning: multi-character literal with 5 characters exceeds 'int' size of 4 bytes
   21 |     mp['Sunny']='Cloudy';
      |        ^~~~~~~
a.cc:21:17: warning: multi-character literal with 6 characters exceeds 'int' size of 4 bytes
   21 |     mp['Sunny']='Cloudy';
      |                 ^~~~~~~~
a.cc:22:8: warning: multi-character literal with 6 characters exceeds 'int' size of 4 bytes
   22 |     mp['Cloudy']='Rainy';
      |        ^~~~~~~~
a.cc:22:18: warning: multi-character literal with 5 characters exceeds 'int' size of 4 bytes
   22 |     mp['Cloudy']='Rainy';
      |                  ^~~~~~~
a.cc:23:8: warning: multi-character literal with 5 characters exceeds 'int' size of 4 bytes
   23 |     mp['Rainy']='Sunny';
      |        ^~~~~~~
a.cc:23:17: warning: multi-character literal with 5 characters exceeds 'int' size of 4 bytes
   23 |     mp['Rainy']='Sunny';
      |                 ^~~~~~~
a.cc: In function 'int main()':
a.cc:21:7: error: no match for 'operator[]' (operand types are 'std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >' and 'int')
   21 |     mp['Sunny']='Cloudy';
      |       ^
In file included from /usr/include/c++/14/map:63,
                 from a.cc:5:
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = std::__cxx11::basic_string<char>; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; mapped_type = std::__cxx11::basic_string<char>; key_type = std::__cxx11::basic_string<char>]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >::key_type&' {aka 'const std::__cxx11::basic_string<char>&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = std::__cxx11::basic_string<char>; _Tp = std::__cxx11::basic_string<char>; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; mapped_type = std::__cxx11::basic_string<char>; key_type = std::__cxx11::basic_string<char>]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'int' to 'std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >::key_type&&' {aka 'std::__cxx11::basic_string<char>&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:22:7: error: no match for 'operator[]' (operand types are 'std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >' and 'int')
   22 |     mp['Cloudy']='Rainy';
      |       ^
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = std::__cxx11::basic_string<char>; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; mapped_type = std::__cxx11::basic_string<char>; key_type = std::__cxx11::basic_string<char>]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >::key_type&' {aka 'const std::__cxx11::basic_string<char>&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = std::__cxx11::basic_string<char>; _Tp = std::__cxx11::basic_string<char>; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; mapped_type = std::__cxx11::basic_string<char>; key_type = std::__cxx11::basic_string<char>]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'int' to 'std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >::key_type&&' {aka 'std::__cxx11::basic_string<char>&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~
a.cc:23:7: error: no match for 'operator[]' (operand types are 'std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >' and 'int')
   23 |     mp['Rainy']='Sunny';
      |       ^
/usr/include/c++/14/bits/stl_map.h:504:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = std::__cxx11::basic_string<char>; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; mapped_type = std::__cxx11::basic_string<char>; key_type = std::__cxx11::basic_string<char>]'
  504 |       operator[](const key_type& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:504:34: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >::key_type&' {aka 'const std::__cxx11::basic_string<char>&'}
  504 |       operator[](const key_type& __k)
      |                  ~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:524:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](key_type&&) [with _Key = std::__cxx11::basic_string<char>; _Tp = std::__cxx11::basic_string<char>; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; mapped_type = std::__cxx11::basic_string<char>; key_type = std::__cxx11::basic_string<char>]'
  524 |       operator[](key_type&& __k)
      |       ^~~~~~~~
/usr/include/c++/14/bits/stl_map.h:524:29: note:   no known conversion for argument 1 from 'int' to 'std::map<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >::key_type&&' {aka 'std::__cxx11::basic_string<char>&&'}
  524 |       operator[](key_type&& __k)
      |                  ~~~~~~~~~~~^~~