Re: One Zero variants_without

How about using a string and shuffle the ones from right to left using substr.

use strict;
use warnings;

my $raCombinations = combinary(4, 7);
print qq{$_\n} for @$raCombinations;

sub combinary
{
    my ($numZeros, $numOnes) = @_;
    my $str = q{0} x $numZeros . q{1} x $numOnes;
    my @combinations = ($str);

    my $leftPtr = 0;
    for my $thisOne ( 1 .. $numOnes )
    {
        for (
               my $offset = $numZeros + $thisOne - 2;
               $offset >= $leftPtr;
               $offset --
            )
        {
            substr $str, $offset, 2, q{10};
            push @combinations, $str;
        }
    $leftPtr ++;
    }

    return \@combinations;
}
[download]

produces

00001111111
00010111111
00100111111
01000111111
10000111111
10001011111
10010011111
10100011111
11000011111
11000101111
11001001111
11010001111
11100001111
11100010111
11100100111
11101000111
11110000111
11110001011
11110010011
11110100011
11111000011
11111000101
11111001001
11111010001
11111100001
11111100010
11111100100
11111101000
11111110000
[download]

I don't know whether this approach will be slower or faster than other suggestions. It's just the first idea that occurred to me.

Cheers,

JohnGG

Comment on Re: One Zero variants_without_repetition Select or Download Code

Replies are listed 'Best First'.
Re^2: One Zero variants_without_repetition by graff (Chancellor) on Aug 08, 2007 at 04:07 UTC
I gather that the OP also wants strings like: `00011011111 00011101111 00011110111 00011111011 00011111101 00011111110 00110011111 00111001111 ...` [download] which your code didn't get around to. (And apparently, expecting to hold all results in memory before outputting them may be unrealistic.)	[reply] [d/l]
Re^2: One Zero variants_without_repetition by thenetfreaker (Friar) on Aug 08, 2007 at 06:13 UTC
You are right about these strings that it doesn't get, as well as: `. . . 01001011111 . . . 11011001011 . . etc` [download] but i don't need to hold them in memory, i simply check each one of them individually and move to the other; but this algorithm surely seems to work Fast. If only to fix it a bit to show every variation like the ones you stated, considering it shall slow in twice or three times, with will be wonderful.	[reply] [d/l]


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Re: One Zero variants_without_repetition