# Python – Pairs with Sum equal to K in tuple list

• Last Updated : 06 Mar, 2020

Sometimes, while working with data, we can have a problem in which we need to find the sum of pairs of tuple list. And specifically the sum that is equal to K. This kind of problem can be important in web development and competitive programming. Lets discuss certain ways in which this task can be performed.

Method #1 : Using loop
This can be solved using loop. This is brute way in which this task is performed. In this, we iterate the list for pair summation and retain whose sum is K.

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning - Basic Level Course

 `# Python3 code to demonstrate ``# Pairs with Sum equal to K in tuple list``# using loop`` ` `# Initializing list``test_list ``=` `[(``4``, ``5``), (``6``, ``7``), (``3``, ``6``), (``1``, ``2``), (``1``, ``8``)]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# Initializing K ``K ``=` `9`` ` `# Pairs with Sum equal to K in tuple list``# using loop``res ``=` `[]``for` `ele ``in` `test_list:``    ``if` `ele[``0``] ``+` `ele[``1``] ``=``=` `K: ``        ``res.append(ele)`` ` `# printing result ``print` `(``"List after extracting pairs equal to K : "` `+` `str``(res))`
Output :

```The original list is : [(4, 5), (6, 7), (3, 6), (1, 2), (1, 8)]
List after extracting pairs equal to K : [(4, 5), (3, 6), (1, 8)]
```

Method #2 : Using list comprehension
This is yet another way in which this task can be performed. In this, we extract the elements in similar method as above, the difference is that we perform this task as shorthand and in one line.

 `# Python3 code to demonstrate ``# Pairs with Sum equal to K in tuple list``# using list comprehension`` ` `# Initializing list``test_list ``=` `[(``4``, ``5``), (``6``, ``7``), (``3``, ``6``), (``1``, ``2``), (``1``, ``8``)]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# Initializing K ``K ``=` `9`` ` `# Pairs with Sum equal to K in tuple list``# using list comprehension``res ``=` `[(ele[``0``], ele[``1``]) ``for` `ele ``in` `test_list ``if` `ele[``0``] ``+` `ele[``1``] ``=``=` `K]`` ` `# printing result ``print` `(``"List after extracting pairs equal to K : "` `+` `str``(res))`
Output :
```The original list is : [(4, 5), (6, 7), (3, 6), (1, 2), (1, 8)]
List after extracting pairs equal to K : [(4, 5), (3, 6), (1, 8)]
```

My Personal Notes arrow_drop_up