Fatal error: Uncaught TypeError: usort(): Argument #1 ($array) must be of type array, null given in /var/www/html/index.php:1868 Stack trace: #0 /var/www/html/index.php(1868): usort(NULL, 'Simplex::cmp_na...') #1 /var/www/html/index.php(2038): Simplex->sort() #2 /var/www/html/index.php(2626): Simplex->run(Object(Location)) #3 {main} thrown in /var/www/html/index.php on line 1868