P1030python
时间: 2023-11-26 10:48:48 浏览: 82
根据提供的引用内容,P1030是一道题目,需要使用Python编写程序来解决。具体来说,这道题目要求我们实现一个字符串的哈夫曼编码,即将给定的字符串转换为哈夫曼编码后输出。其中,哈夫曼编码是一种可变长度编码,通过将出现频率较高的字符用较短的编码表示,从而达到压缩数据的目的。
以下是一个Python实现哈夫曼编码的例子:
```python
from heapq import heappush, heappop, heapify
from collections import defaultdict
def huffman_encoding(s):
# 统计字符出现的频率
freq = defaultdict(int)
for c in s:
freq[c] += 1
# 构建哈夫曼树
heap = [[wt, [sym, ""]] for sym, wt in freq.items()]
heapify(heap)
while len(heap) > 1:
lo = heappop(heap)
hi = heappop(heap)
for pair in lo[1:]:
pair[1] = '0' + pair[1]
for pair in hi[1:]:
pair[1] = '1' + pair[1]
heappush(heap, [lo[0] + hi[0]] + lo[1:] + hi[1:])
# 构建编码表
code = dict(heappop(heap)[1:])
return code
s = input()
code = huffman_encoding(s)
for c in s:
print(code[c], end="")
```
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