/**

单词查找树的节点实现

霍夫曼单词查找树

*/

private static class Node implements Comparable<Node>{

private char ch;

private int freq;

private final Node left;

private final Node right;

Node(char ch, int freq, Node left, Node right){

this.ch = ch;

this.freq = freq;

this.left = left;

this.right = right;

}

public boolean isLeaf(){

return left == null && right == null;

}

public int compareTo(Node that){

return this.freq - that.freq;

}

}