Regex for set

Question

I'd like some help for detecting the following expressions with RegEx

string "(x/x)" where x is any number from 0-999. string "x of x" where x is any number from 0-999.

Typically, the string is a marker for a set, i.e. 4 of 10 things, or (3/5) where the first number is the item and the second number is the total.

Thanks

Answer 1

How about

"\d{1,3}/\d{1,3}"

and

"\d{1,3} of \d{1,3}"

Answer 2

\([0-9]+\/[0-9]+\)

and

[0-9]+ of [0-9]+

Answer 3

See How to match numbers between X and Y with regexp?.

#!/usr/bin/perl

use strict;
use warnings;

my $num_re = qr/[0-9]|[1-9][0-9]|[1-9][0-9]{2}/;
for my $s qw( 1/10 100/500 a/456) {
    if (my ($x, $y) = $s =~ m{^($num_re)/($num_re)$}) {
     print "x is $x and y is $y\n";
    } else {
     print "$s does not match\n";
    }
}

or just

^([0-9]|[1-9][0-9]|[1-9][0-9]{2})\/([0-9]|[1-9][0-9]|[1-9][0-9]{2})$

if you don't mind violating DRY.