Re: Need Help On Ada95 Problem

["Alex" <alex@foo.invalid>]

Oh, I see how you're confused. Once you get the value of each digit in
the PIN, though, it doesn't matter that the 3-4-5 corresponding to
V-A-L  isn't in ASCII order. . . it's still just a direct index-based
lookup (just off-by-one because Ada Strings are indexed starting at 1
rather than 0).

Shark8 wrote:

> On Feb 9, 7:36�pm, BrianG <m...@null.email> wrote:
> > On 02/08/2012 09:01 PM, Shark8 wrote:
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > > On Feb 8, 7:03 pm, Will<willmann...@gmail.com> �wrote:
> > >> I am new to Ada and need help on an exercise for school. �Can
> > anyone >> help. �The problem is as follows ( you can skip all the
> > build up >> background A Christmas Story references):
> > 
> > >> Problem 1: Secret Decoder Ring
> > ...
> > >> � � � number wheel -> � � �0 �1 �2 �3 �4 �5 �6 �7 �8 �9
> > >> � � � letter wheel -> � � �U �R �O �V �A �L �T �I �N �E
> > 
> > >> So, for example, Randy encrypts the PIN 9537 as ELVI.
> > 
> > >> Complete the function Encrypt(PIN) that takes a 4-digit PIN (as a
> > >> string) and returns the corresponding 4-letter code (also as a
> > >> string).
> > 
> > >> Note: It would be possible to convert digits to letters using a
> > giant >> IF statement, but don't do this. Instead, the letter wheel
> > is given to >> you as a string, so use each digit to read the
> > appropriate letter from >> the string.
> > 
> > > Alright this is actually a simple problem; there are several ways
> > > to go about this,
> > > but let's play to Ada's strengths and use types.
> > 
> > ...
> > > Reading the problem the note says:
> > > It would be possible to convert digits to letters using a giant
> > > IF statement, but don't do this. Instead, the letter wheel is
> > > given to you as a string, so use each digit to read the
> > > appropriate letter from the string.
> > 
> > > Meaning that they're hinting strongly that you use the CASE
> > > statement.
> > 
> > I don't see why this would require either an if or a case.
> > 
> > --
> > ---
> > BrianG
> > 000
> > @[Google's email domain]
> > .com
> 
> Well, you COULD use Ada's Maps; but that's just going to do the same
> thing: you still have to define the mapping.
> You can't just index into Character (via 'POS, 'VAL and index-
> manipulation) because the mapping isn't sequential;
> or even partly-sequential in the ASCII codes.
> 
> See the (3,4,5) association with (V,A,L) and (6,7,8) with (T,I,N).