# Python – Remove Elements in K distance with N

• Last Updated : 11 Oct, 2020

Given a list, remove all elements which are within K distance with N.

Input : test_list = [4, 5, 9, 1, 10, 6, 13 ], K = 3, N = 5
Output : [9, 1, 10, 13]
Explanation : 4 is removed as 5 – 4 = 1 < 3, hence its within distance.

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Input : test_list = [1, 10, 6, 13 ], K = 3, N = 5
Output : [1, 10, 13]
Explanation : 4 is removed as 5 – 4 = 1 < 3, hence its within distance.

Method #1 : Using list comprehension

In this, we extract only those elements which are at safe distance by magnitude K to N using comparisons using list comprehension.

## Python3

 `# Python3 code to demonstrate working of ``# Remove Elements in K distance with N``# Using list comprehension`` ` `# initializing list``test_list ``=` `[``4``, ``5``, ``9``, ``1``, ``10``, ``6``, ``13` `]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing K ``K ``=` `3`` ` `# initializing N ``N ``=` `5`` ` `# checking for elements in safe zone with respect to N``res ``=` `[ele ``for` `ele ``in` `test_list ``if` `ele < N ``-` `K ``or` `ele > N ``+` `K]`` ` `# printing result ``print``(``"Filtered elements : "` `+` `str``(res))`
Output
```The original list is : [4, 5, 9, 1, 10, 6, 13]
Filtered elements : [9, 1, 10, 13]
```

Method #2 : Using filter() + lambda

In this, task of filtering is done using filter() and lambda function.

## Python3

 `# Python3 code to demonstrate working of ``# Remove Elements in K distance with N``# Using filter() + lambda`` ` `# initializing list``test_list ``=` `[``4``, ``5``, ``9``, ``1``, ``10``, ``6``, ``13` `]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing K ``K ``=` `3`` ` `# initializing N ``N ``=` `5`` ` `# checking for elements in safe zone with respect to N``res ``=` `list``(``filter``(``lambda` `ele : ele < N ``-` `K ``or` `ele > N ``+` `K, test_list))`` ` `# printing result ``print``(``"Filtered elements : "` `+` `str``(res))`
Output
```The original list is : [4, 5, 9, 1, 10, 6, 13]
Filtered elements : [9, 1, 10, 13]
```

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