public static String formatBrainFuck(String input) {
	input = input.replaceAll("[\r\n\t ]+", "");
	StringBuilder builder = new StringBuilder(input);
	int layer = 0;
	int[] layers = new int[input.length()];
	for (int index = 0; index < builder.length(); index++) {
		char c = builder.charAt(index);
		if (c == '[')
			layers[index] = ++layer;
		else if (c == ']')
			layers[index] = --layer;
		else
			layers[index] = layer;
	}
	for (layer = 0; layer < Arrays.stream(layers).max().orElse(0); layer++) {
		builder.append('\n');
		boolean open = false;
		for (int index = 0; index < layers.length; index++) {
			if (layer < layers[index])
				if (!open) {
					builder.append('[');
					open = true;
				} else
					builder.append('_');
			else {
				if (open) {
					builder.append(']');
					open = false;
				} else
					builder.append(' ');
			}
		}
	}
	return builder.toString();
}