use strict;
use warnings;
use List::Util 'shuffle';
use Time::HiRes 'time';

# Return index to biggest element.

sub reisinge {
    [ sort { $_[$b] <=> $_[$a] } 0 .. $#_ ]->[0];
}

sub GrandFather {
    my $idxMax = 0;
    $_[$idxMax] > $_[$_] or $idxMax = $_ for 1 .. $#_;
    $idxMax;
}

sub biggest_elm {
    my ($idxMax,$idx) = (0,0);
    ($_[$idxMax] > $_ or $idxMax = $idx), $idx++ for @_;
    $idxMax;
}

srand 0;

my @list = shuffle 1..4e5;

for my $code (qw( reisinge GrandFather biggest_elm )) {
    no strict 'refs';
    my ($start, $idx) = (time, $code->(@list));

    printf "Index %d, Seconds (%-11s): %0.03f\n",
        $idx, $code, time - $start;
}