Question

让我们考虑这个示例文本文件：

Level: 1
Level: 1
Level: 2
Level: 2
Level: 2
Level: 3
Level: 3
Level: 1
Level: 2
Level: 2
Level: 1

我需要使用提供的级别数据将这些行转换为从属计数（不包括下属的下属）结果应如下所示：

:0
:3
:0
:0
:2
:0
:0
:2
:0
:0
:0

我的第一个想法是将文本文件转换为XML并使用简单的xml解析器技术作为解决方案，但后来我记得python有时可以做出神奇的事情，并且如果有人知道如何以“pythonic”方式做到这一点，则会想到寻求建议（没有xml帮助）

由于

Answer 1

可能的解决方案：

input_text = """Level: 1
Level: 1
Level: 2
Level: 2
Level: 2
Level: 3
Level: 3
Level: 1
Level: 2
Level: 2
Level: 1"""

# Parse input text into a list of levels (as int)
levels = []
for line in input_text.split('\n'):
    try:
        levels.append(int(line.split(': ', 1)[-1]))
    except Exception:
        pass # skip line

# Compute how many children each node has by counting the number of
# consecutive subsequent lines that belong to exactly the next level
counters = [0] * len(levels)
for i, level in enumerate(levels):
    for other in levels[i + 1:]:
        if other == level + 1:
            counters[i] += 1
        elif other == level:
            break

print '\n'.join(':%d' % c for c in counters)

将级别深度转换为从属计数

1 个答案: