you don't need to shuffle the full array, just splice two random elements:
# my @numbers = (1..10); oops, thanks RMGir!
my @a = (1..10);
my $r1 = splice @a, rand(@a), 1;
my $r2 = splice @a, rand(@a), 1;
update: splice can be an expensive operation as it has to move all the elements inside the array from the insertion point upwards (complexity O(N)).
A more efficient approach is:
sub pop_any (\@) {
my $a = shift;
my $r = int rand(@$a);
@{$a}[$r, 0] = @{$a}[0, $r] if $r;
shift @$a
}
my @a = (1..10);
my $r1 = pop_any @a;
my $r2 = pop_any @a;
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