Sort using a custom comparator

Sort an array (or list) of strings in order of descending length, then in ascending lexicographic order. Use a sorting facility provided by the language/library, combined with your own callback comparison function.

C

Compiler: GCC 4.0.1

Platform: BSD

#include <stdlib.h>
#include <strings.h>

int mycmp(const void *s1, const void *s2)
{
    int d;
    const char *l = *(const char **)s1, *r = *(const char **)s2;
    if (d = strlen(r) - strlen(l))
        return d;
    return strcasecmp(l, r);
}

int main()
{
    char *strings[8] = {"Here", "are", "some", "sample", "strings", "to", "be", "sorted"};
    qsort(strings, 8, sizeof(char *), mycmp);
}

Haskell

Interpreter: GHCi

import List
import Char

mycmp s1 s2 = case compare (length s2) (length s1) of
                 EQ -> compare (map toLower s1) (map toLower s2)
                 x  -> x

strings = ["Here", "are", "some", "sample", "strings", "to", "be", "sorted"]
sorted = sortBy mycmp strings

Perl

Interpreter: perl 5.8.6

sub mycmp { length $b <=> length $a or lc $a cmp lc $b }

@strings = ("Here", "are", "some", "sample", "strings", "to", "be", "sorted");
@sorted = sort mycmp @strings;

PHP

Interpreter: PHP 4.4.4 CLI

<?php
function mycmp($s1, $s2)
{
    if ($d = strlen($s2) - strlen($s1))
        return $d;
    return strcasecmp($s1, $s2);
}

$strings = array("Here", "are", "some", "sample", "strings", "to", "be", "sorted");
usort($strings, "mycmp");
?>