给定n个权值作为n个叶子结点，构造一棵二叉树，若带权路径长度达到最小，称这样的二叉树为最优二叉树，也称为哈夫曼树(Huffman tree)。,Given n weights as a the n leaf node, construct a binary tree, with the right path length to a minimum, said such a binary tree for the optimal binary tree, also known as Huffman tree (Huffman tree).