目标是在给定整数列表的情况下找到递增/单调数组。结果组中的每个项目都必须比前一个项目增加 +1
给定一个输入:
x = [7, 8, 9, 10, 6, 0, 1, 2, 3, 4, 5]
我需要找到数量递增的组并实现:
increasing_numbers = [(7,8,9,10), (0,1,2,3,4,5)]
最终还有越来越多的数字:
len(list(chain(*increasing_numbers)))
还有组的长度:
increasing_num_groups_length = [len(i) for i in increasing_numbers]
我尝试了以下方法来获取递增的数字:
>>> from itertools import tee, chain
>>> def pairwise(iterable):
... a, b = tee(iterable)
... next(b, None)
... return zip(a, b)
...
>>> x = [8, 9, 10, 11, 7, 1, 2, 3, 4, 5, 6]
>>> set(list(chain(*[(i,j) for i,j in pairwise(x) if j-1==i])))
set([1, 2, 3, 4, 5, 6, 8, 9, 10, 11])
>>> len(set(list(chain(*[(i,j) for i,j in pairwise(x) if j-1==i]))))
10
但是我无法保持顺序和递增的组数。
如何实现 increasing_numbers
组整数元组以及 increasing_num_groups_length
?
另外,是否有此类/类似问题的名称?
已编辑
我想出了这个解决方案,但它非常冗长,我相信有一种更简单的方法可以实现 increasing_numbers
输出:
>>> from itertools import tee, chain
>>> def pairwise(iterable):
... a, b = tee(iterable)
... next(b, None)
... return zip(a, b)
...
>>> x = [8, 9, 10, 11, 7, 1, 2, 3, 4, 5, 6]
>>> boundary = iter([0] + [i+1 for i, (j,k) in enumerate(pairwise(x)) if j+1!=k] + [len(x)])
>>> [tuple(x[i:next(boundary)]) for i in boundary]
[(8, 9, 10, 11), (1, 2, 3, 4, 5, 6)]
是否有更 pythonic/更简洁的方法来做到这一点?
另一个输入/输出示例:
[在]:
[17, 17, 19, 20, 21, 22, 0, 1, 2, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 14, 14, 28, 29, 30, 31, 32, 33, 34, 35, 36, 40]
[输出]:
[(19, 20, 21, 22), (0, 1, 2), (4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14), (28, 29, 30, 31, 32, 33, 34, 35, 36)]
最佳答案
编辑:
这是一个代码高尔夫解决方案(142 个字符):
def f(x):s=[0]+[i for i in range(1,len(x)) if x[i]!=x[i-1]+1]+[len(x)];return [x[j:k] for j,k in [s[i:i+2] for i in range(len(s)-1)] if k-j>1]
扩展版:
def igroups(x):
s = [0] + [i for i in range(1, len(x)) if x[i] != x[i-1] + 1] + [len(x)]
return [x[j:k] for j, k in [s[i:i+2] for i in range(len(s)-1)] if k - j > 1]
评论版本:
def igroups(x):
# find the boundaries where numbers are not consecutive
boundaries = [i for i in range(1, len(x)) if x[i] != x[i-1] + 1]
# add the start and end boundaries
boundaries = [0] + boundaries + [len(x)]
# take the boundaries as pairwise slices
slices = [boundaries[i:i + 2] for i in range(len(boundaries) - 1)]
# extract all sequences with length greater than one
return [x[start:end] for start, end in slices if end - start > 1]
原方案:
不确定这算作“pythonic”还是“不太冗长”:
def igroups(iterable):
items = iter(iterable)
a, b = None, next(items, None)
result = [b]
while b is not None:
a, b = b, next(items, None)
if b is not None and a + 1 == b:
result.append(b)
else:
if len(result) > 1:
yield tuple(result)
result = [b]
print(list(igroups([])))
print(list(igroups([0, 0, 0])))
print(list(igroups([7, 8, 9, 10, 6, 0, 1, 2, 3, 4, 5])))
print(list(igroups([8, 9, 10, 11, 7, 1, 2, 3, 4, 5, 6])))
print(list(igroups([9, 1, 2, 3, 1, 1, 2, 3, 5])))
输出:
[]
[]
[(7, 8, 9, 10), (0, 1, 2, 3, 4, 5)]
[(8, 9, 10, 11), (1, 2, 3, 4, 5, 6)]
[(1, 2, 3), (1, 2, 3)]
关于python - 在列表中查找递增数字组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/33402355/