两个int对象之间的条件检查

时间:2018-11-21 08:54:14

标签: python recursion conditional

我在for循环中迭代,构造一个列表,同时将该列表的最后一个数字与另一个数字进行比较。

我希望我的代码查看列表的最后一项是否小于被比较的项目,如果是,则将其添加到列表的末尾,然后继续。

如果列表的最后一项较大,我想弹出列表的最后一项。然后,我想对它施加相同的条件。

这是我的代码,它不起作用,在弹出列表的最后一项后,它不会重新检查条件条件。

if tempList:
    lastNum=tempList[-1]
    #############################################
    if element < lastNum:
        incList.append(tempList)
        tempList.pop()
        lastNum=tempList[-1]
   #############################################

    elif lastNum < element:                                               
        tempList.append(element)
        continue

2 个答案:

答案 0 :(得分:0)

您可以将其捆绑为一个函数:

def append_if_lower_else_pop_end_from_list_until_lower(l, num):
    """Add num to l if l[-1] < num, else pop() from l until"""
    while l and l[-1] > num:
        l.pop()
    l.append(num)

    # this is not strictly needed - lists are mutable so you are mutating it
    # returning it would only make sense for chaining off it with other methods
    return l 

k = [3,5,7,9,11,13]
print(k)
append_if_lower_else_pop_end_from_list_until_lower(k, 10)
print(k)
append_if_lower_else_pop_end_from_list_until_lower(k, 6)
print(k)
append_if_lower_else_pop_end_from_list_until_lower(k, 10)
print(k)
append_if_lower_else_pop_end_from_list_until_lower(k, 10)
print(k)
append_if_lower_else_pop_end_from_list_until_lower(k, -10)
print(k)

输出:

[3, 5, 7, 9, 11, 13]  # start
[3, 5, 7, 9, 10]      # after adding 10
[3, 5, 6]             # after addding 6
[3, 5, 6, 10]         # after adding 10
[3, 5, 6, 10, 10]     # after adding 10 again
[-10]                 # after adding -10 

为什么还要返回列表:链接示例:

k = [3,5,17,9,11,13]
append_if_lower_else_pop_end_from_list_until_lower(k, 10).sort()
print(k)

输出:

[3, 5, 9, 10, 17]

答案 1 :(得分:-1)

尝试一下:

yourlist = [3,1,4]
n = 1
resultlist = yourlist[:-1] if yourlist[-1]>=n else yourlist+[n]
print(resultlist)
n = 5
resultlist = yourlist[:-1] if yourlist[-1]>=n else yourlist+[n]
print(resultlist)

输出: [3,1]

[3,1,4,5]