#! /usr/bin/perl -w
use strict;

use Benchmark qw(timethese);

sub zeit_mit_func {

# old function calling localtime several times (slightly modified)
    my $wtag = ("So","Mo","Di","Mi","Do","Fr","Sa")[(localtime)[6]];
    my $mtag = sprintf("%02d", (localtime)[3]);
    my $monat = sprintf("%02d", (localtime)[4]+1);
    my $jahr = (localtime)[5] + 1900;
    my $stunde = sprintf("%02d", (localtime)[2]);
    my $minute = sprintf("%02d", (localtime)[1]);
    my $zeit = "$wtag $mtag\.$monat\.$jahr - $stunde\:$minute";
    return $zeit;
}
sub zeit_mit_array {
# new function calling localtime only once assigning it to an array
    my @zeit = localtime;
    my $wtag = ("So","Mo","Di","Mi","Do","Fr","Sa")[$zeit[6]];
    my $mtag = sprintf("%02d", $zeit[3]);
    my $monat = sprintf("%02d", $zeit[4]+1);
    my $jahr = $zeit[5] + 1900;
    my $stunde = sprintf("%02d", $zeit[2]);
    my $minute = sprintf("%02d", $zeit[1]);
    my $zeit = "$wtag $mtag\.$monat\.$jahr - $stunde\:$minute";
    return $zeit;
}
timethese (1E5, {
    'func' => \&zeit_mit_func,
    'array' => \&zeit_mit_array,
});