Re^6: A Beginner Needs Homework help

lol.

I realized what you meant and changed the program so it would die if not read. what I'm trying to work on now is the pattern matching. Upon reading my textbook I don't really think I need substitution. What I need my program to do is to recognize similar words with their numbers and add them together, otherwise look over the word (and associate number) but print them anyway.

($info=~ /(\w+ (-?\d+ )+)/)

That should match any word with its number, since \w is for word charters and \d is for numbers. + is for one or more of the same to match.. the and ? is so that the last number can still be counted. the dash in front of it is undefined to me by my text book.. (elements of programming with perl)

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Re^7: A Beginner Needs Homework help by Anonymous Monk on Apr 11, 2014 at 21:37 UTC
lol... I don't really think I need substitution... :) sounds good ... That should ... the dash in front of it is undefined to me by my text book.. (elements of programming with perl) What does it say a regular expression is composed of? What is the special characters like "?" called? So if its not the same kind of character as the special "?" character, its what kind of character? :) Here is what rxrx says about the pattern `(`The start of a capturing block ($1) `\w+`Match an identifier character, one-or-more times (as many as possible) `(`The start of a capturing block ($2) `-?`Match a literal '-' character, one-or-zero times (as many as possible) `\d+`Match a digit, one-or-more times (as many as possible) `)+`The end of $2 (matching one-or-more times (as many as possible)) `)`The end of $1 Its pretty close except it doesn't explain the literal space character ... it does show that in the next step If you give rxrx a string, it will go a step further and show you how the regex matches To do it run rxrx then paste `'red:27 yellow:102 green:311 yellow:12 blue:45'` then paste `/(\w+ (-?\d+ )+)/` then type m then enter and keep hitting space to see the next step Here is what a step looks like `Trying literal whitespace ('\N{SPACE}') \| V /(\w+ (-?\d+ )+)/ \| V 'red:27 yellow:102 green:311 yellow:12 blue:45' [Visual of regex at 'rxrx' line 0] [step: 7]` [download] So hopefully you can see what you're missing, its the thing you had in split	[reply] [d/l] [select]

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Re^7: A Beginner Needs Homework help
by Anonymous Monk on Apr 11, 2014 at 21:37 UTC

lol... I don't really think I need substitution...

:) sounds good

... That should ... the dash in front of it is undefined to me by my text book.. (elements of programming with perl)

What does it say a regular expression is composed of? What is the special characters like "?" called? So if its not the same kind of character as the special "?" character, its what kind of character?

:) Here is what rxrx says about the pattern

(The start of a capturing block ($1)
\w+Match an identifier character, one-or-more times (as many as possible)
(The start of a capturing block ($2)
-?Match a literal '-' character, one-or-zero times (as many as possible)
\d+Match a digit, one-or-more times (as many as possible)
)+The end of $2 (matching one-or-more times (as many as possible))
)The end of $1

Its pretty close except it doesn't explain the literal space character ... it does show that in the next step

If you give rxrx a string, it will go a step further and show you how the regex matches

To do it run rxrx

then paste 'red:27 yellow:102 green:311 yellow:12 blue:45'

then paste /(\w+ (-?\d+ )+)/

then type m then enter and keep hitting space to see the next step

Here is what a step looks like

     Trying literal whitespace ('\N{SPACE}')
     |
     V
/(\w+ (-?\d+ )+)/


   |
   V
'red:27  yellow:102  green:311  yellow:12  blue:45'


[Visual of regex at 'rxrx' line 0]         [step: 7]
[download]

So hopefully you can see what you're missing, its the thing you had in split

[reply]
[d/l]
[select]