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# Python – K Maximum elements with Index in List

• Last Updated : 01 Aug, 2020

GIven a List, extract K Maximum elements with their indices.

Input : test_list = [5, 3, 1, 4, 7, 8, 2], K = 2
Output : [(4, 7), (5, 8)]
Explanation : 8 is maximum on index 5, 7 on 4th.

Input : test_list = [5, 3, 1, 4, 7, 10, 2], K = 1
Output : [(5, 10)]
Explanation : 10 is maximum on index 5.

Method #1 : Using sorted() + index()

The combination of above functions provide a way of finding solution to this problem. In this, we initially perform sort and extract K maximum elements, then are encapsulated in tuple with their ordering in original list.

## Python3

 `# Python3 code to demonstrate working of ``# K Maximum elements with Index in List``# Using sorted() + index()`` ` `# initializing list``test_list ``=` `[``5``, ``3``, ``1``, ``4``, ``7``, ``8``, ``2``]`` ` `# printing original list ``print``(``"The original list : "` `+` `str``(test_list))`` ` `# initializing K``K ``=` `3`` ` `# Using sorted() + index()``# using sorted() to sort and slice K maximum elements ``temp ``=` `sorted``(test_list)[``-``K:]``res ``=` `[]``for` `ele ``in` `temp:``     ` `    ``# encapsulating elements with index using index()``    ``res.append((test_list.index(ele), ele))`` ` `# printing result ``print``(``"K Maximum with indices : "` `+` `str``(res))`
Output
```The original list : [5, 3, 1, 4, 7, 8, 2]
K Maximum with indices : [(0, 5), (4, 7), (5, 8)]
```

Method #2 : Using enumerate() + itemgetter()

The combination of above functions can be used to solve this problem. In this, we perform the task of getting indices using enumerate() and itemgetter() is used to get the elements.

## Python3

 `# Python3 code to demonstrate working of``# K Maximum elements with Index in List``# Using enumerate() + itemgetter()``from` `operator ``import` `itemgetter`` ` `# initializing list``test_list ``=` `[``5``, ``3``, ``1``, ``4``, ``7``, ``8``, ``2``]`` ` `# printing original list``print``(``"The original list : "` `+` `str``(test_list))`` ` `# initializing K``K ``=` `3`` ` `# Using enumerate() + itemgetter()``# Making index values pairs at 1st stage``res ``=` `list``(``sorted``(``enumerate``(test_list), key ``=` `itemgetter(``1``)))[``-``K:]`` ` `# printing result``print``(``"K Maximum with indices : "` `+` `str``(res))`
Output
```The original list : [5, 3, 1, 4, 7, 8, 2]
K Maximum with indices : [(0, 5), (4, 7), (5, 8)]
```

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