Python LZW 算法

LZW 压缩算法

string = "thisisthe"dictionary = {chr(i):i for i in range(97,123)} last = 256p = ""result = [] for c in string:    pc = p+c    if pc in dictionary:        p = pc    else:        result.append(dictionary[p])        dictionary[pc] = last        last += 1        p = c if p != '':    result.append(dictionary[p]) print(result)

以上代码运行结果为：

[116, 104, 105, 115, 258, 256, 101]

LZW 解压缩算法

dictionary = {i:chr(i) for i in range(97,123)}last = 256arr = [97, 97, 98, 256, 258, 257, 259] result = []p = arr.pop(0)result.append(dictionary[p]) for c in arr:    if c in dictionary:        entry = dictionary[c]    result.append(entry)    dictionary[last] = dictionary[p] + entry[0]    last += 1    p = c print(''.join(result))

以上代码运行结果为：

aabaabaabaab