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# Python | Find missing elements in List

• Last Updated : 19 Jun, 2019

Sometimes, we can get elements in range as input but some values are missing in otherwise consecutive range. We might have a use case in which we need to get all the missing elements. Let’s discuss certain ways in which this can be done.

Method #1 : Using list comprehension
We can perform the task of finding missing elements using the range function to get the maximum element fill and then insert the elements if there is a miss.

 `# Python3 code to demonstrate``# Finding missing elements in List``# using list comprehension`` ` `# initializing list``test_list ``=` `[``3``, ``5``, ``6``, ``8``, ``10``]`` ` `# printing original list``print``(``"The original list : "` `+` `str``(test_list))`` ` `# using list comprehension``# Finding missing elements in List``res ``=` `[ele ``for` `ele ``in` `range``(``max``(test_list)``+``1``) ``if` `ele ``not` `in` `test_list]`` ` `# print result``print``(``"The list of missing elements : "` `+` `str``(res))`
Output :
```The original list : [3, 5, 6, 8, 10]
The list of missing elements : [0, 1, 2, 4, 7, 9]
```

Method #2 : Using `set()`
This problem can also be performed using the properties of difference of set and then getting the elements that are missing in a range.

 `# Python3 code to demonstrate``# Finding missing elements in List``# Using set()`` ` `# initializing list``test_list ``=` `[``3``, ``5``, ``6``, ``8``, ``10``]`` ` `# printing original list``print``(``"The original list : "` `+` `str``(test_list))`` ` `# Using set()``# Finding missing elements in List``res ``=` `list``(``set``(``range``(``max``(test_list) ``+` `1``)) ``-` `set``(test_list))`` ` `# print result``print``(``"The list of missing elements : "` `+` `str``(res))`
Output :
```The original list : [3, 5, 6, 8, 10]
The list of missing elements : [0, 1, 2, 4, 7, 9]
```

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