protected function getStringsByPrefix(array $strings)
	{
		$byPrefix = [];
		foreach ($strings as $string)
		{
			$byPrefix[$string[0]][] = $string;
		}

		return $byPrefix;
	}
protected function getStringsByPrefix(array $strings)
	{
		$byPrefix = [];
		foreach ($strings as $string)
		{
			$byPrefix[$string[0]][] = $string;
		}

		return $byPrefix;
	}
protected function getStringsByPrefix ( array $ strings ) { $ byPrefix = [ ] ; foreach ( $ strings as $ string ) { $ byPrefix [ $ string [ 0 ] ] [ ] = $ string ; } return $ byPrefix ; }
Return given strings grouped by their first element

NOTE: assumes that this pass is run before the first element of any string could be replaced

@param  array[] $strings
@return array[]
Return given strings grouped by their first element