/**
* Same as above function, but using StringBuilder instead of int. This is only for readability
* purpose. <br>
* This is for traversing the tree and assigning the huffman code when leaf node is encountered
*
* @param rootNode Root node of the tree
* @param code Empty stringBuilder, which
*/
static void huffManEncoding(CharFreq rootNode, StringBuilder code) {
if (!rootNode.isLeafNode()) {
// While going left append 0
code.append(0);
huffManEncoding(rootNode.left, code);
// while going right, append 1
code.append(1);
huffManEncoding(rootNode.right, code);
} else {
rootNode.huffMan = Integer.parseInt(code.toString());
}
// remove the last character while going back
if (code.length() > 0) code.deleteCharAt(code.length() - 1);
}
/**
* @param rootNode
* @param code Starting with 0
* @return It is used for just calculating the huffrecursion value further. It's is not returning
* any final value
*/
static int huffManEncoding(CharFreq rootNode, int code) {
if (!rootNode.isLeafNode()) {
// While going left left shift one bit, so that 0 will be appended
// at last
code = code << 1;
code = huffManEncoding(rootNode.left, code);
// while going right, left shift 1 bit and Or with 1, so that 1 will
// be appended at last
code = (code << 1) | 1;
code = huffManEncoding(rootNode.right, code);
} else {
rootNode.huffMan = code;
}
// While going back right shift by one bit, to discard it
return code >> 1;
}
