Treat Lower case letters the same as Upper case letters using ASCII

[dmitrip]

hello

i am writing a program that has the user input a word and it outputs if the word is a palindrome(reads the same backwards and forwards) or if it is not a palindrome.
Now what i am trying to make it do is treat upper case letters the same as lower case letters, so for example chr(97) = chr(65) which means that 'a' is the same letter as 'A'
so how could i get the program to treat the letters the same no matter if its upper case or lower case.


thank you very much.

[CodeMonkey2000]

First look at the ASCII chart (it's some where in the turing reference). Look at the ASCII for lower case letters, and the higher case. Notice a pattern? All the higher case letters are 32 characters lower than their higher case counter part (i.e. chr(65)='A' and chr(97)='a' and the difference is 32 ). Use this idea to solve the problem.

[[Gandalf]]

Or you can use the Str module built into Turing and convert all your words to either all caps (Str.Upper("hi")) or all lower case (Str.Lower("HI")). That way when you make your palindrome checks it will treat the letters the same whether or not they are in caps.

[dmitrip]

this is the bit of code from my program that should convert all the letters into lowercase letters but it but it isnt working.

help will be very appreciteated, and i tried the above but i been trying for an hour now and this is only as far as i got.
thank you

code:

for i : 1 .. length (word)         count (i) := word (1 + length (word) - i)         right (i) := word (i)     end for     for i : 1 .. length (word)           if right (i) = count (i) then             palindrome += 1             if ord(word(i))>65 and ord (word(i))<90 then             word := chr (ord(word(i))-32)             if palindrome = length (word) then                 put "The word is a palindrome"                   end if             end if         end if                     end for     if palindrome not= length (word) then         put "The word is not a palindrome"             end if

[[Gandalf]]

While it may be good to know, you don't need to work with ord() and chr() to solve your problem. The Str.Lower() function returns whichever string it is given in all lower case. Try it:

Turing:

put Str.Lower ("THIS IS ALL IN CAPS, OR IS IT?")

Or a bit more in depth:

Turing:

var foo : string := "bar" var baz : string := "BaR" put "foo = ", foo put "baz = ", baz put "Str.Lower (baz) = ", Str.Lower (baz) put "foo = baz is ", foo = baz put "foo = Str.Lower (baz) is ", foo = Str.Lower (baz)

[ericfourfour]

dmitrip look up at the post above your last one. The simplest answer is right there.

Edit: err... posted exactly the same time as gandalf.

[dmitrip]

the thing is i am using turing for windows by holt softwares and it give me an error that says: 'Lower' is not in the export list of 'Str'

[dmitrip]

i appreciate everybody trying to help me, i started playing around with the code a little and i wrote it in a little bit diffrenet way

here it is:

code:

var word : string     var lowercase : int  % for loop that     for i : 1 .. length (word)         count (i) := word (1 + length (word) - i)         right (i) := word (i)     end for     for i : 1 .. length (word)           if right (i) = count (i) then             palindrome += 1             if ord(word(i))< 97 then                              lowercase := ord (word(i))+32            put chr(ord (lowercase(i)))..                         if palindrome = length (word) then                 put "The word is a palindrome"                   end if         end if         end if

this is the same code as above but i rewrote it in a different way , but it gives me an error in the line put chr(ord (lowercase(i))).. anybody know what the problem might be, if needed i can post the full code.

thanks alot everybody

[CodeMonkey2000]

I think you get the error because your version of turing doesn't have Str.Lower defined (Iknow mine doesn't). I wrote a Lower function a while back for my compsci class.

Turing:

function Lower (str : string) : string     var newString : string := ""     for x : 1 .. length (str)         if ord (str (x)) >= 65 and ord (str (x)) <= 90 then             newString += chr (ord (str (x)) + 32)         else             newString += str (x)         end if     end for     result newString end Lower put Lower ("ABLEH! ahHHHHHHh! FIZBUZZZZZ!!!")

[dmitrip]

CodeMonkey2000 i really appreciate your help and i like your sentence on the bottom of your tag but i just have one more question about this topic. now when i input the word lets say "ABBA" it tells me its a palindrome and its great cause thats what it suppose to do but than when i input "Abba" it tells me that its not a palindrome when it should tell me its a palindrome, i am gonna post my full code, its a big long but most of the lines you can skip reading cause they are straight forward

code:

function Lower (str : string) : string     var newString : string := ""     for x : 1 .. length (str)         if ord (str (x)) >= 65 and ord (str (x)) <= 90 then             newString += chr (ord (str (x)) + 32)         else             newString += str (x)         end if     end for     result newString end Lower loop         var word : string     var lowercase : int     put "Please Enter a word: " ..     get word             var count : array 1 .. length (word) of string     var right : array 1 .. length (word) of string     var palindrome : int := 0           for i : 1 .. length (word)         count (i) := word (1 + length (word) - i)         right (i) := word (i)     end for       for i : 1 .. length (word)           if right (i) = count (i) then             palindrome += 1      word := Lower (word(i))                         if palindrome = length (word) then                 put "The word is a palindrome"                   end if         end if             end for                 if palindrome not= length (word) then         put "The word is not a palindrome"             end if      end loop

thank you very much for all the help!

[Clayton]

I think you're trying to complicate this a bit much. Just have a for loop that checks each letter from the outside in, 1 character deeper for each iteration. If the two characters match, go on to the next iteration of the loop, otherwise, exit the loop. Ideally this will be in a function that returns a boolean value to ease the coding of the main line.

[CodeMonkey2000]

What is the significance of this:

Turing:

word := Lower (word (i))

?
Take that line out, and place

Turing:

word := Lower (word)

after you get the value of word from the user. [/code]

[Clayton]

Check out the String Manipulation tutorial that is in the Turing Walkthrough to answer any other questions after reading this.

Basically, what

code:

word := Lower (word (i))

means is that you are setting word to equal the lowercase equivalent of character "i" in the string word. A string is more or less an array of characters mashed together to create a string. Following this, using word (i) makes sense because word is basically an array of characters, so word (i) is accessing the ith element of word.

code:

word := Lower (word)

is actually putting the entire string word through the function Lower in this case. Not just a character, the whole thing.

EDIT: I read that as a question as what the difference between the two was.

[dmitrip]

ok i took it out but that still doenst solve my problem, if i type in "Abba" for word it still says its not a palindrome when it is

thanks alot

[CodeMonkey2000]

By the way, you can simplify this code A LOT. Anyway try this and see if it works:

Turing:

function Lower (str : string) : string     var newString : string := ""     for x : 1 .. length (str)         if ord (str (x)) >= 65 and ord (str (x)) <= 90 then             newString += chr (ord (str (x)) + 32)         else             newString += str (x)         end if     end for     result newString end Lower loop         var word : string     var lowercase : int     put "Please Enter a word: " ..     get word       word:= Lower (word)%this is important     var count : array 1 .. length (word) of string     var right : array 1 .. length (word) of string     var palindrome : int := 0     for i : 1 .. length (word)         count (i) := word (1 + length (word) - i)         right (i) := word (i)     end for       for i : 1 .. length (word)         if right (i) = count (i) then             palindrome += 1     % word := Lower (word(i))             if palindrome = length (word) then                 put "The word is a palindrome"             end if         end if     end for     if palindrome not= length (word) then         put "The word is not a palindrome"     end if end loop