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      std::basic_string<CharT,Traits,Allocator>::find_last_of

      From cppreference.com
      <cpp‎ |string‎ |basic string
       
       
       
      std::basic_string
       
      size_type find_last_of(const basic_string& str,
                              size_type pos= npos)const;
      		 (1)(noexcept since C++11)
      (constexpr since C++20)
      size_type find_last_of(const CharT* s,
                              size_type pos, size_type count)const;
      		 (2)(constexpr since C++20)
      size_type find_last_of(const CharT* s, size_type pos= npos)const;
      		 (3)(constexpr since C++20)
      size_type find_last_of( CharT ch, size_type pos= npos)const;
      		 (4)(noexcept since C++11)
      (constexpr since C++20)
      template<class StringViewLike>

      size_type
          find_last_of(const StringViewLike& t,

                        size_type pos= npos)constnoexcept(/* see below */);
      		 (5)(since C++17)
      (constexpr since C++20)

      Finds the last character equal to one of characters in the given character sequence. The exact search algorithm is not specified. The search considers only the range[​0​, pos]. If none of the characters in the given character sequence is present in the range,npos will be returned.

      1) Finds the last character equal to one of characters instr.
      2) Finds the last character equal to one of characters in range[s, s+ count). This range can include null characters.
      If[s, s+ count) is not avalid range, the behavior is undefined.
      3) Finds the last character equal to one of characters in character string pointed to bys. The length of the string is determined by the first null character usingTraits::length(s).
      If[s, s+ Traits::length(s)) is not avalid range, the behavior is undefined.
      4) Finds the last character equal toch.
      5) Implicitly convertst to a string viewsv as if bystd::basic_string_view<CharT, Traits> sv= t;, then finds the last character equal to one of characters insv.
      This overload participates in overload resolution only ifstd::is_convertible_v<const StringViewLike&,
                           std::basic_string_view<CharT, Traits>>       istrue andstd::is_convertible_v<const StringViewLike&,const CharT*> isfalse.

      In all cases, equality is checked by callingTraits::eq.

      Contents

      [edit]Parameters

      str - string identifying characters to search for
      pos - position at which the search is to finish
      count - length of character string identifying characters to search for
      s - pointer to a character string identifying characters to search for
      ch - character to search for
      t - object (convertible tostd::basic_string_view) identifying characters to search for

      [edit]Return value

      Position of the found character ornpos if no such character is found.

      [edit]Exceptions

      1,4) Throws nothing.
      5)
      noexcept specification:  
      noexcept(std::is_nothrow_convertible_v<const T&,std::basic_string_view<CharT, Traits>>)

      If an exception is thrown for any reason, this function has no effect (strong exception safety guarantee).

      [edit]Example

      Run this code
      #include <iostream>#include <string> int main(){conststd::string path="/root/config";autoconst pos= path.find_last_of('/');constauto leaf= path.substr(pos+1); std::cout<< leaf<<'\n';}

      Output:

      config

      [edit]Defect reports

      The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

      DRApplied toBehavior as publishedCorrect behavior
      LWG 141C++98overload (1) could only returnnpos ifpos>= size()the search range is
      [​0​, size()) in this case
      LWG 847C++98there was no exception safety guaranteeadded strong exception safety guarantee
      LWG 2064C++11overloads(3,4) were noexceptremoved
      LWG 2946C++17overload(5) caused ambiguity in some casesavoided by making it a template
      P1148R0C++11
      C++17      		noexcept for overloads(4,5) were
      accidentally dropped by LWG2064/LWG2946      		restored

      [edit]See also

      finds the first occurrence of the given substring
      (public member function)[edit]
      find the last occurrence of a substring
      (public member function)[edit]
      find first occurrence of characters
      (public member function)[edit]
      find first absence of characters
      (public member function)[edit]
      find last absence of characters
      (public member function)[edit]
      find last occurrence of characters
      (public member function ofstd::basic_string_view<CharT,Traits>)[edit]
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