# Python – Differential Sort String Numbers and Alphabets

• Last Updated : 08 Mar, 2023

Given a List String, Reorder List, with Sorted Alphabets followed by Sorted Strings.

Input : test_list = [“1”, “G”, “10”, “L”, “9”, “K”, “4”]
Output : [‘G’, ‘K’, ‘L’, ‘1’, ‘4’, ‘9’, ’10’]
Explanation : Alphabets sorted, succeeded by sorted digits.

Input : test_list = [“1”, “G”, “10”, “L”, “9”]
Output : [‘G’, ‘L’, ‘1’, ‘9’, ’10’]
Explanation : Alphabets sorted, succeeded by sorted digits.

Method #1 : Using isnumeric() + loop

In this, we separate numeric and alphabetic characters, using isnumeric(), and then perform sort on each list, then perform join of both lists for obtaining result. Works with only 1 digit numbers string.

## Python3

 `# Python3 code to demonstrate working of``# Differential Sort String Numbers and Alphabets``# Using isnumeric() + loop` `# initializing list``test_list ``=` `[``"1"``, ``"G"``, ``"7"``, ``"L"``, ``"9"``, ``"M"``, ``"4"``]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `numerics ``=` `[]``alphabets ``=` `[]``for` `sub ``in` `test_list:``    ` `    ``# checking and inserting in respective container``    ``if` `sub.isnumeric():``        ``numerics.append(sub)``    ``else``:``        ``alphabets.append(sub)` `# attaching lists post sort``res ``=` `sorted``(alphabets) ``+` `sorted``(numerics)` `# printing result``print``(``"The Custom sorted result : "` `+` `str``(res))`

Output

```The original list is : ['1', 'G', '7', 'L', '9', 'M', '4']
The Custom sorted result : ['G', 'L', 'M', '1', '4', '7', '9']```

Method #2 : Using sorted() + isnumeric()

This is one liner way to solve this problem, it checks for numerics using isnumeric, and sorted() is used to perform sort(). Converts elements to integers and tests, can handle more than 1 digit numbers.

## Python3

 `# Python3 code to demonstrate working of``# Differential Sort String Numbers and Alphabets``# Using sorted() + isnumeric()` `# initializing list``test_list ``=` `[``"100"``, ``"G"``, ``"74"``, ``"L"``, ``"98"``, ``"M"``, ``"4"``]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `# using int() to type convert to integer``# using sorted() to perform sort operation``res ``=` `sorted``(test_list, key ``=` `lambda` `ele: (ele.isnumeric(), ``int``(ele) ``if` `ele.isnumeric() ``else` `ele))` `# printing result``print``(``"The Custom sorted result : "` `+` `str``(res))`

Output

```The original list is : ['100', 'G', '74', 'L', '98', 'M', '4']
The Custom sorted result : ['G', 'L', 'M', '4', '74', '98', '100']```

Time Complexity: O(n*log(n))

Auxiliary Space: O(n)

Method #3 : Using isalpha()+sort()+extend() methods

## Python3

 `# Python3 code to demonstrate working of``# Differential Sort String Numbers and Alphabets``# initializing list``test_list ``=` `[``"1"``, ``"G"``, ``"7"``, ``"L"``, ``"9"``, ``"M"``, ``"4"``]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `numerics ``=` `[]``alphabets ``=` `[]``for` `sub ``in` `test_list:``    ``# checking and inserting in respective container``    ``if` `sub.isalpha():``        ``alphabets.append(sub)``    ``else``:``        ``numerics.append(sub)` `# attaching lists post sort``alphabets.sort()``numerics.sort()``alphabets.extend(numerics)` `# printing result``print``(``"The Custom sorted result : "` `+` `str``(alphabets))`

Output

```The original list is : ['1', 'G', '7', 'L', '9', 'M', '4']
The Custom sorted result : ['G', 'L', 'M', '1', '4', '7', '9']```

Time Complexity : O(N)
Auxiliary Space : O(N)

Method 4: Using list comprehension +  isnumeric()

The idea is to separate the numbers and alphabets into two separate lists and then sorting them separately before concatenating them.

Below is the implementation:

## Python3

 `# Python3 code to demonstrate working of``# Differential Sort String Numbers and Alphabets``# Using two separate lists` `# initializing list``test_list ``=` `[``"1"``, ``"G"``, ``"7"``, ``"L"``, ``"9"``, ``"M"``, ``"4"``]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `# separating numbers and alphabets``num_list ``=` `[``int``(x) ``for` `x ``in` `test_list ``if` `x.isnumeric()]``alpha_list ``=` `[x ``for` `x ``in` `test_list ``if` `not` `x.isnumeric()]` `# sorting the lists``num_list.sort()``alpha_list.sort()` `# concatenating the lists``res ``=` `alpha_list ``+` `[``str``(x) ``for` `x ``in` `num_list]` `# printing result``print``(``"The Custom sorted result : "` `+` `str``(res))`

Output

```The original list is : ['1', 'G', '7', 'L', '9', 'M', '4']
The Custom sorted result : ['G', 'L', 'M', '1', '4', '7', '9']```

Time complexity: O(n*log(n)) because the sorting of both lists takes O(n*log(n)) time.
Auxiliary space: O(n) because we are creating two separate lists to store the numbers and alphabets, which can take up to n space.

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