#! perl -slw
use strict;
use List::Util qw[ shuffle ];

use Inline C => 'DATA';

$^W = 0;

my $max = 100;
my @values = 1 .. $max;
my @values_mixed = shuffle( @values );
my @top = topN( 5, sub { $_[ 0 ] <=> $_[ 1 ]; }, \@values_mixed );
print "@top";

__END__
__C__
int callComp( SV* cmp, SV* a, SV* b ) {
	int rv;
	dSP;ENTER; SAVETMPS; PUSHMARK(SP);

	XPUSHs( newSViv( SvIVX( a ) ) );
	XPUSHs( newSViv( SvIVX( b ) ) );
	PUTBACK;

	call_sv( cmp, G_SCALAR );
	SPAGAIN;

	rv = POPi;

	FREETMPS;LEAVE;
	return rv;
}

void topN( int n, SV* comp, AV*data ) {
    int *topN;
    int len = av_len( data );
    int i, j, k;

    Inline_Stack_Vars;
    Newz( 1, topN, n + 1, SV* );
	for( i = 0; i < n+1; i++ ) topN[ i ] = newSViv( 0 );
    
    for( i = 0; i <= len; i++ )    {
        SV* val = *av_fetch( data, i, 0 );
        for( j = 0; j < n; j++ ) {
            int cmp = callComp( comp, topN[ j ], val );
            if( cmp >= 0 ) continue;
            if( cmp < 0 ) {
                for( k = n; k > j; k-- ) topN[ k ] = topN[ k-1 ];
                topN[ j ] = val;
                break;
            }
        }
    }
    
    Inline_Stack_Reset;
    for( i = 0; i < n; i++ )
        Inline_Stack_Push( sv_2mortal( newSVsv( topN[ i ] ) ) );
    
    Safefree( topN );
    Inline_Stack_Done;
}