/in/cipher.cpp:93:13: error: multi-character character constant [-Werror=multichar]
   if(str == '100'){
             ^~~~~
/in/cipher.cpp:96:18: error: multi-character character constant [-Werror=multichar]
   else if(str == '200'){
                  ^~~~~
/in/cipher.cpp:99:18: error: multi-character character constant [-Werror=multichar]
   else if(str == '000'){
                  ^~~~~
/in/cipher.cpp: In function 'char IntToChar(std::__cxx11::string)':
/in/cipher.cpp:93:10: error: no match for 'operator==' (operand types are 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' and 'int')
   if(str == '100'){
      ~~~~^~~~~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:64:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_pair.h:448:5: note: candidate: template<class _T1, class _T2> constexpr bool std::operator==(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)
     operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
     ^~~~~~~~
/usr/include/c++/7/bits/stl_pair.h:448:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::pair<_T1, _T2>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:302:5: note: candidate: template<class _Iterator> constexpr bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)
     operator==(const reverse_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:302:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::reverse_iterator<_Iterator>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:340:5: note: candidate: template<class _IteratorL, class _IteratorR> constexpr bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)
     operator==(const reverse_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:340:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::reverse_iterator<_Iterator>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:1121:5: note: candidate: template<class _IteratorL, class _IteratorR> constexpr bool std::operator==(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)
     operator==(const move_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:1121:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::move_iterator<_IteratorL>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:1127:5: note: candidate: template<class _Iterator> constexpr bool std::operator==(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)
     operator==(const move_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:1127:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::move_iterator<_IteratorL>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/char_traits.h:40:0,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/postypes.h:216:5: note: candidate: template<class _StateT> bool std::operator==(const std::fpos<_StateT>&, const std::fpos<_StateT>&)
     operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
     ^~~~~~~~
/usr/include/c++/7/bits/postypes.h:216:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::fpos<_StateT>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/string:41:0,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/allocator.h:146:5: note: candidate: template<class _T1, class _T2> bool std::operator==(const std::allocator<_CharT>&, const std::allocator<_T2>&)
     operator==(const allocator<_T1>&, const allocator<_T2>&)
     ^~~~~~~~
/usr/include/c++/7/bits/allocator.h:146:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::allocator<_CharT>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/string:41:0,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/allocator.h:152:5: note: candidate: template<class _Tp> bool std::operator==(const std::allocator<_CharT>&, const std::allocator<_CharT>&)
     operator==(const allocator<_Tp>&, const allocator<_Tp>&)
     ^~~~~~~~
/usr/include/c++/7/bits/allocator.h:152:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::allocator<_CharT>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/basic_string.h:48:0,
                 from /usr/include/c++/7/string:52,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/string_view:450:5: note: candidate: template<class _CharT, class _Traits> constexpr bool std::operator==(std::basic_string_view<_CharT, _Traits>, std::basic_string_view<_CharT, _Traits>)
     operator==(basic_string_view<_CharT, _Traits> __x,
     ^~~~~~~~
/usr/include/c++/7/string_view:450:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::basic_string<char>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/basic_string.h:48:0,
                 from /usr/include/c++/7/string:52,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/string_view:456:5: note: candidate: template<class _CharT, class _Traits> constexpr bool std::operator==(std::basic_string_view<_CharT, _Traits>, std::__detail::__idt<std::basic_string_view<_CharT, _Traits> >)
     operator==(basic_string_view<_CharT, _Traits> __x,
     ^~~~~~~~
/usr/include/c++/7/string_view:456:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::basic_string<char>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/basic_string.h:48:0,
                 from /usr/include/c++/7/string:52,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/string_view:462:5: note: candidate: template<class _CharT, class _Traits> constexpr bool std::operator==(std::__detail::__idt<std::basic_string_view<_CharT, _Traits> >, std::basic_string_view<_CharT, _Traits>)
     operator==(__detail::__idt<basic_string_view<_CharT, _Traits>> __x,
     ^~~~~~~~
/usr/include/c++/7/string_view:462:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   mismatched types 'std::basic_string_view<_CharT, _Traits>' and 'int'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/string:52:0,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/basic_string.h:6009:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6009:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>' and 'int'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/string:52:0,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/basic_string.h:6017:5: note: candidate: template<class _CharT> typename __gnu_cxx::__enable_if<std::__is_char<_Tp>::__value, bool>::__type std::operator==(const std::__cxx11::basic_string<_CharT>&, const std::__cxx11::basic_string<_CharT>&)
     operator==(const basic_string<_CharT>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6017:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   mismatched types 'const std::__cxx11::basic_string<_CharT>' and 'int'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/string:52:0,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/basic_string.h:6031:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const _CharT*, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator==(const _CharT* __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6031:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   mismatched types 'const _CharT*' and 'std::__cxx11::basic_string<char>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/string:52:0,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/basic_string.h:6043:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)
     operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6043:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   mismatched types 'const _CharT*' and 'int'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/ios_base.h:46:0,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/cipher.cpp:2:
/usr/include/c++/7/system_error:292:3: note: candidate: bool std::operator==(const std::error_code&, const std::error_code&)
   operator==(const error_code& __lhs, const error_code& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:292:3: note:   no known conversion for argument 1 from 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' to 'const std::error_code&'
/usr/include/c++/7/system_error:297:3: note: candidate: bool std::operator==(const std::error_code&, const std::error_condition&)
   operator==(const error_code& __lhs, const error_condition& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:297:3: note:   no known conversion for argument 1 from 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' to 'const std::error_code&'
/usr/include/c++/7/system_error:304:3: note: candidate: bool std::operator==(const std::error_condition&, const std::error_code&)
   operator==(const error_condition& __lhs, const error_code& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:304:3: note:   no known conversion for argument 1 from 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' to 'const std::error_condition&'
/usr/include/c++/7/system_error:311:3: note: candidate: bool std::operator==(const std::error_condition&, const std::error_condition&)
   operator==(const error_condition& __lhs,
   ^~~~~~~~
/usr/include/c++/7/system_error:311:3: note:   no known conversion for argument 1 from 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' to 'const std::error_condition&'
In file included from /usr/include/c++/7/bits/locale_facets.h:48:0,
                 from /usr/include/c++/7/bits/basic_ios.h:37,
                 from /usr/include/c++/7/ios:44,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/cipher.cpp:2:
/usr/include/c++/7/bits/streambuf_iterator.h:204:5: note: candidate: template<class _CharT, class _Traits> bool std::operator==(const std::istreambuf_iterator<_CharT, _Traits>&, const std::istreambuf_iterator<_CharT, _Traits>&)
     operator==(const istreambuf_iterator<_CharT, _Traits>& __a,
     ^~~~~~~~
/usr/include/c++/7/bits/streambuf_iterator.h:204:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::istreambuf_iterator<_CharT, _Traits>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/x86_64-linux-gnu/c++/7/bits/c++allocator.h:33:0,
                 from /usr/include/c++/7/bits/allocator.h:46,
                 from /usr/include/c++/7/string:41,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/ext/new_allocator.h:155:5: note: candidate: template<class _Tp> bool __gnu_cxx::operator==(const __gnu_cxx::new_allocator<_Tp>&, const __gnu_cxx::new_allocator<_Tp>&)
     operator==(const new_allocator<_Tp>&, const new_allocator<_Tp>&)
     ^~~~~~~~
/usr/include/c++/7/ext/new_allocator.h:155:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const __gnu_cxx::new_allocator<_Tp>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:869:5: note: candidate: template<class _Iterator, class _Container> bool __gnu_cxx::operator==(const __gnu_cxx::__normal_iterator<_Iterator, _Container>&, const __gnu_cxx::__normal_iterator<_Iterator, _Container>&)
     operator==(const __normal_iterator<_Iterator, _Container>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:869:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const __gnu_cxx::__normal_iterator<_Iterator, _Container>'
   if(str == '100'){
             ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:862:5: note: candidate: template<class _IteratorL, class _IteratorR, class _Container> bool __gnu_cxx::operator==(const __gnu_cxx::__normal_iterator<_IteratorL, _Container>&, const __gnu_cxx::__normal_iterator<_IteratorR, _Container>&)
     operator==(const __normal_iterator<_IteratorL, _Container>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:862:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:93:13: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const __gnu_cxx::__normal_iterator<_IteratorL, _Container>'
   if(str == '100'){
             ^~~~~
/in/cipher.cpp:94:10: error: invalid conversion from 'const char*' to 'char' [-fpermissive]
     ch = "J";
          ^~~
/in/cipher.cpp:96:15: error: no match for 'operator==' (operand types are 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' and 'int')
   else if(str == '200'){
           ~~~~^~~~~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:64:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_pair.h:448:5: note: candidate: template<class _T1, class _T2> constexpr bool std::operator==(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)
     operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
     ^~~~~~~~
/usr/include/c++/7/bits/stl_pair.h:448:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:96:18: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::pair<_T1, _T2>'
   else if(str == '200'){
                  ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:302:5: note: candidate: template<class _Iterator> constexpr bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)
     operator==(const reverse_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:302:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:96:18: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::reverse_iterator<_Iterator>'
   else if(str == '200'){
                  ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:340:5: note: candidate: template<class _IteratorL, class _IteratorR> constexpr bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)
     operator==(const reverse_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:340:5: note:   template argument deduction/substitution failed:
/in/cipher.cpp:96:18: note:   'std::__cxx11::string {aka std::__cxx11::basic_string<char>}' is not derived from 'const std::reverse_iterator<_Iterator>'
   else if(str == '200'){
                  ^~~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/string:40,
                 from /in/cipher.h:5,
                 from /in/cipher.cpp:1:
/usr/include/c++/7/bits/stl_iterator.h:1121:5: note: candidate: template<class _IteratorL, class _IteratorR> constexpr bool std::operator==(const std: