# Python – Extract Rear K digits from Numbers

• Difficulty Level : Basic
• Last Updated : 11 Oct, 2020

Given an Integer list, extract rear K digits from it.

Input : test_list = [5645, 23567, 34543, 87652, 2342], K = 2
Output : [45, 67, 43, 52, 42]
Explanation : Last 2 digits extracted.

Input : test_list = [5645, 23567, 34543, 87652, 2342], K = 4
Output : [5645, 3567, 4543, 7652, 2342]
Explanation : Last 4 digits extracted.

Method #1 : Using list comprehension + % operator

In this technique, we modulo each number with 10^K to get the desired last K digits of each number.

## Python3

 `# Python3 code to demonstrate working of ``# Extract Rear K digits from Numbers``# Using list comprehension + % operator `` ` `# initializing list``test_list ``=` `[``5645``, ``23567``, ``34543``, ``87652``, ``2342``]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing K ``K ``=` `3`` ` `# Getting remainder for each element``res ``=` `[ele ``%` `(``10` `*``*` `K) ``for` `ele ``in` `test_list]`` ` `# printing result ``print``(``"Rear K digits of elements ? : "` `+` `str``(res))`

Output

```The original list is : [5645, 23567, 34543, 87652, 2342]
Rear K digits of elements ? : [645, 567, 543, 652, 342]
```

Method #2 : Using str() + slicing

In this, we perform task of getting rear elements using list slicing, and str() is used to convert each element to string.

## Python3

 `# Python3 code to demonstrate working of ``# Extract Rear K digits from Numbers``# Using str() + slicing `` ` `# initializing list``test_list ``=` `[``5645``, ``23567``, ``34543``, ``87652``, ``2342``]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing K ``K ``=` `3`` ` `# getting integer using int() after slicing string``res ``=` `[``int``(``str``(idx)[``-``K:]) ``for` `idx ``in` `test_list]`` ` `# printing result ``print``(``"Rear K digits of elements ? : "` `+` `str``(res))`

Output

```The original list is : [5645, 23567, 34543, 87652, 2342]
Rear K digits of elements ? : [645, 567, 543, 652, 342]
```

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