# Python | Farthest point on horizontal lines in 2D plane

Sometimes, while in competitive programming, we might be facing a problem which is of geometry domain and works with x-y coordinate system. The list of tuple can be used to store the same. And along with this, there might be a problem in which we need point with max value of x axis with similar y axis i.e farthest point on horizontal lines. Let’s discuss certain ways to discuss this problem.

Method : Using list comprehension + `max()`
This is a generic brute force method applied to get the max x axis point for common y axis, made as 1 liner using list comprehension. The `max()` is used to find the max of x axis element.

 `# Python3 code to demonstrate working of ` `# Farthest point on horizontal lines in 2D plane ` `# Using list comprehension + max() ` `from` `collections ``import` `defaultdict ` ` `  `# initializing list ` `test_list ``=` `[(``1``, ``6``), (``4``, ``6``), (``2``, ``6``), (``6``, ``8``), (``1``, ``8``), (``2``, ``9``)] ` ` `  `# printing original list ` `print``(``"The original list is : "` `+`  `str``(test_list)) ` ` `  `# Using list comprehension + max() ` `# Farthest point on horizontal lines in 2D plane ` `temp ``=` `defaultdict(``list``) ` `for` `key, val ``in` `test_list: ` `   ``temp[val].append(key) ` `res ``=` `[(key, val) ``for` `key, val ``in` `test_list ``if` `max``(temp[val]) ``=``=` `key] ` ` `  `# Printing result ` `print``(``"The list after filtering just maximum points on lines : "` `+`  `str``(res)) `

Output :

```The original list is : [(1, 6), (4, 6), (2, 6), (6, 8), (1, 8), (2, 9)]
The list after filtering just maximum points on lines : [(4, 6), (6, 8), (2, 9)]
```
My Personal Notes arrow_drop_up Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Article Tags :

Be the First to upvote.

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.