CODEWITHSUNDEEP
delphi
Amber
Amber

Reputation: 171

Count characters and substring in words

I have to read an unknown quantity of words and terminate the program when the word "last" is typed in. I have to:

Problem: The only problem I have is displaying the number of names that end with "anne". It displays 0, except if I only enter the word "anne", then it displays 1.

Note:

My code:

unit Ess_U;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ComCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    redOut: TRichEdit;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
Var wrd : string;
    Scount, dcount, Namecount : integer;
begin
redOut.clear;
   Scount := 0;
   dcount := 0;
   Namecount := 0;


   repeat
    wrd := inputbox ('Input words', 'Enter any word', '');

    if (Pos('S',wrd) > 0) AND (wrd[1] = 'S') then
     begin
     inc(Scount);
     end

    else if (Pos('d',wrd) > 0) AND (wrd[length(wrd)] = 'd') then
     begin
     inc(dcount);
     end

    else if copy(wrd, length(wrd)-4,4) = 'anne' then
     begin
     inc(Namecount);
     end;

    until (wrd = 'last');

    redOut.Lines.Add ('The number of names that begin with the letter "S" is ' + inttostr(Scount));
    redOut.Lines.Add ('The number of names that end with the letter "d"  is ' + inttostr(dcount));
    redOut.Lines.Add ('The number of names that begin with "anne" is ' + inttostr(Namecount));
end;

end.

enter code here

Upvotes: 3

Views: 280

Answers (2)

quasoft
quasoft

Reputation: 5438

You should be using StartsText and EndsText from StrUtils to check if a string starts or ends with a text, instead of manually calling Pos and Copy. (or AnsiStartsText and AnsiEndsText)

Add StrUtils to your uses clause and change the section with conditions like that:

 ...
 uses StrUtils, ...;
 ...

 if (StartsText('S', wrd)) then
 begin
   Inc(Scount);
 end

 if (EndsText('d', wrd)) then
 begin
   Inc(dcount);
 end

 if (StartsText('anne', wrd)) then
 begin
   Inc(Namecount);
 end;

The StrUtils unit has the following useful routines:

  • StartsText - determines if the substring ASubText begins the string AText, case insensitive comparison;
  • StartsStr - same as StartsText, but case sensitive;
  • EndsText - determines if the substring ASubText ends the string AText, case insensitive comparison;
  • EndsStr - same as EndsStr, but case sensitive;

Upvotes: 4

MartynA
MartynA

Reputation: 30715

You've already had an answer that shows you another way to do what you were attempting, using library functions. That's fine (assuming your Delphi version has them), but there's an unresolved aspect to your question.

You said "Problem: The only problem I have is displaying the number of names that end with "anne". It displays 0, except if I only enter the word "anne", then it displays 1."

Now, a key part of coding is learning to debug, and a key part of that is accurate observation and knowing to construct a reproducible test case.

Try this:

Change the first line of your repeat loop to read:

wrd := 'xanne'; //inputbox ('Input words', 'Enter any word', '');

and change the test for 'anne' to read

else begin
  wrd := copy(wrd, length(wrd)-4,4);
  Caption := wrd;
  if wrd = 'anne' then
    begin
     inc(Namecount);
    end;
end;

then, put a breakpoint on the line 

  wrd := copy(wrd, length(wrd)-4,4);

and press F9 to compile and run your program.

When the debugger stops at the breakpoint, keep pressing F8 (to single-step through the code.

You'll soon see what's wrong, namely that 

 copy(wrd, length(wrd)-4,4)

does not equal 'anne' when wrd starts off as 'xanne'. I'll leave you to work out why not, because I think you'll find that a bit more instructive than just finding out about a new-to-you library function.

Btw, this sort of thing tends to happen when you try testing a program by typing inputs over and over. That's why I've said to modify you code temporarily, so that you're starting from a known input, not one you may have mistyped (or even had the CapsLock on by mistake and not noticed).

Upvotes: 6

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