Hi,

So I was doing a code challenge and it's about sorting a string in numerical order based on the integer as part of the string, e.g:

"is2 Thi1s T4est 3a"  -->  "Thi1s is2 3a T4est"

I did it by creating a list with placeholder values and then assigned the values based on the number identified, see:

def order(sentence):
  temp = sentence.split()
  result = [0 for x in range(len(temp))]

  for item in temp:
    for char in item:
      if char.isnumeric():
        num = int(char)
        result[num-1] = item

  return " ".join(result)

I was just looking at other solutions and saw this cool one liner:

return sorted(temp, key=lambda w:sorted(w))

But I don't quite understand how it works :(

I have used the key= argument in the past, for example sorting by the size of the string, i.e key=len

The lambda uses a variable, w and passes it through sorted, but how does that sort by the number included in the string?

Hi there, I was learning about the lambda/anonymous functions. And I came across this example which sorts a list:

lst = ["Mouse Keyboard", "Router Hub", "CPU UPS"]
lst.sort(key = lambda each: each.split(" ")[-1].lower())
print(lst)

# Which returns output:-
# ['Router Hub', 'Mouse Keyboard', 'CPU UPS']

I tried to google this but was not successful enough. If someone kindly enlightens me on what the key in the sort() function is for. With the google search, I concluded that it takes a function as input. So, the input here will be the 2nd word of each item in the list. But I'm unable to figure out how the sorting function is performed.