Task: Abbreviations, easy


C++: #include <algorithm>
#include <cctype>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>

const char* command_table =
  "Add ALTer  BAckup Bottom  CAppend Change SCHANGE  CInsert CLAst COMPress COpy "
  "COUnt COVerlay CURsor DELete CDelete Down DUPlicate Xedit EXPand EXTract Find "
  "NFind NFINDUp NFUp CFind FINdup FUp FOrward GET Help HEXType Input POWerinput "
  "Join SPlit SPLTJOIN  LOAD  Locate CLocate  LOWercase UPPercase  LPrefix MACRO "
  "MErge MODify MOve MSG Next Overlay PARSE PREServe PURge PUT PUTD  Query  QUIT "
  "READ  RECover REFRESH RENum REPeat  Replace CReplace  RESet  RESTore  RGTLEFT "
  "RIght LEft  SAVE  SET SHift SI  SORT  SOS  STAck STATus  TOP TRAnsfer Type Up";

class command {
public:
    command(const std::string&, size_t);
    const std::string& cmd() const { return cmd_; }
    size_t min_length() const { return min_len_; }
    bool match(const std::string&) const;
private:
    std::string cmd_;
    size_t min_len_;
};


command::command(const std::string& cmd, size_t min_len)
    : cmd_(cmd), min_len_(min_len) {}


bool command::match(const std::string& str) const {
    size_t olen = str.length();
    return olen >= min_len_ && olen <= cmd_.length()
        && cmd_.compare(0, olen, str) == 0;
}


void uppercase(std::string& str) {
    std::transform(str.begin(), str.end(), str.begin(),
        [](unsigned char c) -> unsigned char { return std::toupper(c); });
}

size_t get_min_length(const std::string& str) {
    size_t len = 0, n = str.length();
    while (len < n && std::isupper(static_cast<unsigned char>(str[len])))
        ++len;
    return len;
}

class command_list {
public:
    explicit command_list(const char*);
    const command* find_command(const std::string&) const;
private:
    std::vector<command> commands_;
};

command_list::command_list(const char* table) {
    std::vector<command> commands;
    std::istringstream is(table);
    std::string word;
    while (is >> word) {
        
        size_t len = get_min_length(word);
        
        uppercase(word);
        commands_.push_back(command(word, len));
    }
}

const command* command_list::find_command(const std::string& word) const {
    auto iter = std::find_if(commands_.begin(), commands_.end(),
        [&word](const command& cmd) { return cmd.match(word); });
    return (iter != commands_.end()) ? &*iter : nullptr;
}

std::string test(const command_list& commands, const std::string& input) {
    std::string output;
    std::istringstream is(input);
    std::string word;
    while (is >> word) {
        if (!output.empty())
            output += ' ';
        uppercase(word);
        const command* cmd_ptr = commands.find_command(word);
        if (cmd_ptr)
            output += cmd_ptr->cmd();
        else
            output += "*error*";
    }
    return output;
}

int main() {
    command_list commands(command_table);
    std::string input("riG   rePEAT copies  put mo   rest    types   fup.    6       poweRin");
    std::string output(test(commands, input));
    std::cout << " input: " << input << '\n';
    std::cout << "output: " << output << '\n';
    return 0;
}










Ada: with Ada.Characters.Handling;
with Ada.Containers.Indefinite_Vectors;
with Ada.Strings.Fixed;
with Ada.Strings.Maps.Constants;
with Ada.Text_IO;

procedure Abbreviations_Easy is

   package Command_Vectors
   is new Ada.Containers.Indefinite_Vectors (Index_Type   => Positive,
                                             Element_Type => String);
   use Command_Vectors;

   Commands : Vector;

   procedure Append (Word_List : String) is
      use Ada.Strings;
      First : Positive := Word_List'First;
      Last  : Natural;
   begin
      loop
         Fixed.Find_Token (Word_List,
                           Set   => Maps.Constants.Letter_Set,
                           From  => First,
                           Test  => Inside,
                           First => First,
                           Last  => Last);
         exit when Last = 0;
         Commands.Append (Word_List (First .. Last));
         exit when Last = Word_List'Last;
         First := Last + 1;
      end loop;
   end Append;

   function Match (Word : String) return String is
      use Ada.Strings;
      use Ada.Characters.Handling;
      Upper_Word   : constant String := To_Upper (Word);
      Prefix_First : Positive;
      Prefix_Last  : Natural;
   begin
      if Word = "" then
         return "";
      end if;

      for Command of Commands loop
         Fixed.Find_Token (Command, Maps.Constants.Upper_Set, Inside,
                           Prefix_First, Prefix_Last);
         declare
            Upper_Prefix  : constant String  := Command (Prefix_First .. Prefix_Last);
            Upper_Command : constant String  := To_Upper (Command);
            Valid_Length  : constant Boolean := Word'Length >= Upper_Prefix'Length;
            Match_Length  : constant Natural := Natural'Min (Word'Length,
                                                             Command'Length);
            Valid_Match   : constant Boolean
              := Fixed.Head (Upper_Word, Upper_Word'Length)
                = Fixed.Head (Upper_Command, Upper_Word'Length);
         begin
            if Valid_Length and Valid_Match then
               return Upper_Command;
            end if;
         end;
      end loop;
      return "*error*";
   end Match;

   procedure Put_Match (To : String) is
      use Ada.Text_IO;
      M : constant String := Match (To);
   begin
      Put ("Match to '");  Put (To);
      Put ("' is '");      Put (M);
      Put_Line ("'");
   end Put_Match;

   procedure A (Item : String) renames Append;
begin
   A ("Add ALTer  BAckup Bottom  CAppend Change SCHANGE  CInsert CLAst COMPress COpy");
   A ("COUnt COVerlay CURsor DELete CDelete Down DUPlicate Xedit EXPand EXTract Find");
   A ("NFind NFINDUp NFUp CFind FINdup FUp FOrward GET Help HEXType Input POWerinput");
   A ("Join SPlit SPLTJOIN  LOAD  Locate CLocate  LOWercase UPPercase  LPrefix MACRO");
   A ("MErge MODify MOve MSG Next Overlay PARSE PREServe PURge PUT PUTD  Query  QUIT");
   A ("READ  RECover REFRESH RENum REPeat  Replace CReplace  RESet  RESTore  RGTLEFT");
   A ("RIght LEft  SAVE  SET SHift SI  SORT  SOS  STAck STATus  TOP TRAnsfer Type Up");

   Put_Match ("riG");
   Put_Match ("rePEAT");
   Put_Match ("copies");
   Put_Match ("put");
   Put_Match ("mo");
   Put_Match ("rest");
   Put_Match ("types");
   Put_Match ("fup.");
   Put_Match ("6");
   Put_Match ("poweRin");
   Put_Match ("");
   Put_Match ("o");
end Abbreviations_Easy;