#!/usr/bin/perl

use strict;
use warnings;

my $path = '/.snapshots123/yabsm/root/hourly/day=2021_03_04,time=21:20
+';

my @nums = $path =~ m/([0-9]{2,4})(?!.*\/)/g;

print "@nums\n";
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Outputs:

2021 03 04 21 20
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