Hi, Today we will be solving leetcode qs 1721 - Swapping Nodes in a Linked List. This qs is really simple. We need to swap the nodes placed at k distance from the start and end of the Linked List. So let's suppose you have a Linked List input as follows: 1 -> 2-> 4 -> 5 -> 7 -> 8 -> 10-> 9 and you are given a k = 2, so the output should be 1 -> 10 -> 4 -> 5 -> 7 -> 8 -> 2 -> 9 so how do we achieve it??? Intuition The most brute force solution one can think of is using Array data structure. For that, we will traverse through linked List and store all the elements in the Array, swap the two numbers and again insert it in theLinked List again. Not bad, but let's deal with it, it is not the optimal solution and far from being as an acceptable solution in interviews. So what can we done instead of that??? Let's try to look deep into the working of Linked List first and how do we traverse it. Linked List is a linear data structure that
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Hi, folks today I am here with an interesting coding problem from Leetcode. *To directly go to the question please click here. So I will walk through the solution. It will be a brute force and an optimized way solution. I will be explaining the optimized way solutions in depth. # Intuition For any substring of length k, we need to find how many vowels are there in it and provide the highest count of all counts of vowels in a substring. Test Case 1 Input k = 2 and s='asjdee' Output - 2 Explanation: As for substring of length k=2, in the string 's' we have 'ee' when the length is k and the vowels count is 2 Test Case 2 Input k=3 and s='aasdiisdwe' Output - 2 Explanation - For all the substrings with length k = 3 we have 'aas' and 'dii' with 2 vowels each in it. Brute Force - Looping (twice) - Gives TLE (Not recommended) # Approach Create a hashmap (dictionary) with all the vowels in it. Loop through the string till len(s)-k element of strin