1．n个叶结点,权分别为w1,w2,• • • ,wn的二叉树中，带权路径长度WPL最小的二叉树叫最优二叉树， 也叫霍夫曼树。

2．霍夫曼算法：1）根据给定的权值{w1,w2,• • • ,wn}构造n个二叉树F={T1,T2,• • • ,Tn}每个Ti只有一个根结点，权为wi。2）在F中选取两棵根结点的权值最小的树 构成一棵新的二叉树，其根的权值为左右子树根的权值的和。3）F中删去这两棵树，加上新得的树。4）重复2）3）直到只剩一棵树。

-1. N leaf nodes, the right to w1, w2, # 8226 # 8226, wn the binary tree, with the right path length WPL smallest binary tree called Optimal binary tree, the tree is also called Hoffman. 2. Hoffman algorithm : 1) According to the weights (w1, w2, # 8226 # 8226 # 8226, wn) n binary tree structure F = (T1, T2, # 8226 # 8226 # 8226, Tn) each only a Ti Root, the right to wi. 2) In 1984 two F Root in the value of the right to the smallest tree constitute a new binary tree, the roots of the right value for the son around the roots and the value of the right. 3) F deleted these two trees, coupled with the new tree. 4) repeat 2) 3) until only a tree.