哈夫曼树又称最优二叉树，是一种带权路径长度最短的二叉树。所谓树的带权路径长度，就是树中所有的叶结点的权值乘上其到根结点的路径长度（若根结点为0层，叶结点到根结点的路径长度为叶结点的层数）。树的带权路径长度记为WPL=(W1*L1+W2*L2+W3*L3+...+Wn*Ln)，N个权值Wi(i=1,2,...n)构成一棵有N个叶结点的二叉树，相应的叶结点的路径长度为Li(i=1,2,...n)。可以证明哈夫曼树的WPL是最小的。-Huffman tree is also called the optimal binary tree is a weighted length of the shortest path tree. The right tree with the so-called path length, is the tree of all the leaf nodes of the right value multiplied by its path length of the root node (root node is 0 if the layer of leaf nodes to root node of the path length for the leaf node layers). Tree path length with the right mind for the WPL = (W1* L1+ W2* L2+ W3* L3+...+ Wn* Ln), N a weight Wi (i = 1,2, ... n) constitute a trees have a N-leaf nodes of the tree, the corresponding leaf nodes of the path length for the Li (i = 1,2, ... n). Huffman tree can prove that the smallest of the WPL.