flatten.js

function fal (input) {
	var output = [], value;
	for (var i = input.length - 1; i >= 0; i--) {
		if (Array.isArray(input[i]) && input[i].length > 0) {
			value = fal(input[i]);
			for (var f = 0; f < value.length; f++)
				output.push(value[f]);			
		} else if( !Array.isArray(input[i]) ){
			output.push(input[i]);
		}
	};
	return output;
}

module.exports = function () {
	var arr = [];
	for (arg in arguments)
		arr.push(arguments[arg]);

	return fal(arr).reverse();
};