So I'm discussing Lottery numbers with my significant other, who says "I don't understand why picking seven numbers costs so much more than six numbers".

So I draw a little diagram like this 

#234567
1#34567
12#4567
123#567
1234#67
12345#7
123456#

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to show that when we pick seven numbers, that includes seven different possible combinations of the six numbers they draw.

"I see", says my significant other, "so seven numbers is like playing seven games, so eight numbers is like having eight games?"

Aha, no, I say, because with eight numbers, you have ... hold on sweetheart, let me write a script for this.

So I write this: 

@numbers = (1..8);
for ( 0 .. 7 ) {
    @outer = @numbers;
    $outer[$_] = '#';
    for ( 0 .. 7 ) {
        @inner = @outer;
        unless ( $inner[$_] eq '#' ) {
            $inner[$_] = '#';
            print @inner, $/;
            $count++;
        }
    }
}

print "$count possible winning combinations\n";

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which dutifully prints out 
##345678
#2#45678
#23#5678
etc

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and shows that a System 8 entry is the same as 56 games.

OK, says the longsuffering Significant Other, "...and with nine numbers?"

At which point I realise my code isn't very smart.

What would other monks write if they wanted to perform this exercise on an array with an arbitrary number of items? And how short could it be? 


($_='kkvvttuubbooppuuiiffssqqffssmmiibbddllffss')
 =~y~b-v~a-z~s;                             print

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In reply to Lottery combinations golf by Cody Pendant

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