http://www.perlmonks.org?node_id=829379


in reply to Re^2: Splitting on a pattern once
in thread Splitting on a pattern once

Is this you are expecting.
Example-1
my $str="1 2 3 4 590"; my ($a,$b)=split(/ ([^ ]+)$/, $str); print "a=$a\nb=$b\n";

Output
a=1 2 3 4
b=590

Example-2
my $str="1:2:3:4:590"; my ($a,$b)=split(/:([^:]+)$/, $str); print "a=$a\nb=$b\n";

Output
a=1:2:3:4
b=590