Re: Generator of integer partitionts of n

[BrowserUk]

#! perl -slw
use strict;

sub xp{ 
    [ @$_, 1 ], 
    @$_ > 1 &&  $_->[ -1 ] < $_->[ -2 ] 
    ? [ @$_[ 0 .. $#$_ -1 ], $_->[ -1 ]+1 ] 
    : () 
}

sub partitions { 
    return unless $_[ 0 ];
    map( xp, partitions( $_[ 0 ] - 1 ) ), [ $_[ 0 ] ];
}

print "@$_" for partitions $ARGV[ 0 ];

__END__
P:\test>386531 6
1 1 1 1 1 1
2 1 1 1 1
2 2 1 1
2 2 2
3 1 1 1
3 2 1
3 3
4 1 1
4 2
5 1
6