Re^2: Simple Arithmetic Question

This is what I have so far I'm not sure how to use the chomp exactly so I'm sure that is wrong. It keeps showing a Global symbol "c" requires explicit package name in lines 14 and 17. I'm sure there are probably multiple errors in the code but I can't figure it out. If you have any pointers that would be great thanks!!

#!/usr/bin/perl
use Modern::Perl;
use strict;
use warnings;

print "input three numbers separated by spaces\n";
my $user_input = <>;
chomp $user_input;
my ($nr1) = $user_input, "$a";

chomp $user_input;
my ($nr2) = $user_input, "$b";

chomp $user_input;
my ($nr3) = $user_input, "$c";


print "The sum of the three numbers is equal to", ($a+$b+$c),"\n";
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Re^3: Simple Arithmetic Question by AnomalousMonk (Archbishop) on Nov 06, 2014 at 04:24 UTC
`print "input three numbers separated by spaces\n"; my $user_input = <>;` [download] This is good as far as it goes: you're getting ~~something~~ \| a string from `STDIN` that is terminated by a newline. `chomp $user_input;` [download] This is good too, except you do it twice more and this is where you start to go off the rails. chomp removes a newline (if present) from the end of a string (well, it's a little more involved than that, but let it stand for now), `$user_input` in this case, so doing it repeatedly will not usually get you anything. For learning/development/debugging, I would advise placing a print statement after this step so you can be sure exactly what you are dealing with: `print "A: '$user_unput' \n";` (In general, develop your code step-by-step and use `print` statements at each successive step to see just what is happening. If weird stuff starts to happen, understand the problem before proceeding.) `my ($nr1) = $user_input, "$a";` [download] This has no meaning. You are assigning `$user_input` to `$nr1` (why?) and interpolating `$a` (which has no value at this point) into a string, which you then throw away: what do you think is happening here? (Update: Two other, similar statements have the same problem.) Please consider these and other points raised so far, write some more code and post again. Update: Do continue to `use strict;` and `use warnings;` in your code (`use Modern::Perl;` includes both of these). They will make learning Perl much easier.	[reply] [d/l] [select]
Re^3: Simple Arithmetic Question by Anonymous Monk on Nov 06, 2014 at 04:02 UTC
Did you wonder about not getting the same warning for `$a` & `$b`(scroll down)? Declare the variable identifiers where they are (sensibly) used via my.	[reply] [d/l] [select]
Re^3: Simple Arithmetic Question by Laurent_R (Canon) on Nov 06, 2014 at 07:26 UTC
Either you get all 3 numbers separated by spaces on one line, chomp it once and then you have to use `split` or some other mechanism to get the individual numbers (the way I did it in my previous post), or you ask three times for one indivudal number from your user, get three times the input, chomp the input three times. `print "give me a number\n"; my $nr1 = <>; chomp $nr1; print "give me a number\n"; my $nr2 = <>; chomp $nr2; print "give me a number\n"; my $nr3 ...` [download]	[reply] [d/l] [select]