Subj : Re: subset function for string in c++
To   : comp.programming
From : Duane Bozarth
Date : Wed Sep 28 2005 05:30 pm

August Karlstrom wrote:
> 
> puzzlecracker wrote:
> > basically, I need to find out wether charecters in string a are subset
> > of string b..
> >
> >
> > example
> >
> >
> > a: rx   b:rwx
> > that shall return true.
> >
> 
> As this group is language independent i chose to write an implementation
> in Oberon:
> 
>     PROCEDURE Subset(a, b: ARRAY OF CHAR): BOOLEAN;
>        VAR j, k: LONGINT;
>     BEGIN
>        j := 0;
>        WHILE a[j] # 0X DO
>           k := 0;
>           WHILE (b[k] # 0X) & (b[k] # a[j]) DO INC(k) END;
>           IF b[k] = 0X THEN RETURN FALSE END;
>           INC(j)
>        END;
>        RETURN TRUE
>     END Subset;
> 
> August

Or,

' Returns true if A is a subset of B, false otherwise.
Function is_subset(a As String, b As String) As Boolean
  is_subset = InStr(a, b) > 0
End Function

or, then again,

logical function is_subset(string, substr) result(flg)
  character (len=*) :: string, substr

  flg = index(string,substr)>0
end function

:)

.