neetcode-150

Problem Statement We have to implement the reorderList function that takes the head node of a linked list as input and reorders its nodes in the format specified below. Given an input list like the following: $$Node_0 \rightarrow Node_1 \rightarrow Node_2 \rightarrow \dots \rightarrow Node_{(n-2)} \rightarrow Node_{(n-1)} \rightarrow Node_n$$ the reorderList function should reorder its nodes as: $$Node_0 \rightarrow Node_n \rightarrow Node_1 \rightarrow Node_{(n-1)} \rightarrow Node_2 \rightarrow Node_{(n-2)} \rightarrow \dots$$...

Problem Statement We have to implement the mergeTwoLists function that takes the head nodes of two sorted linked lists as input and returns the head node of the merged linked list as the output. Optimal Solution To merge both linked lists we can use the two-pointer approach by maintaining an iterator on both linked lists and comparing their values. The smaller value will be selected and inserted at the end of a new list....

Problem Statement We have to implement the reverseList function that takes the head node of a linked list as an input and returns the head node of the reversed linked list in the output. Brute Force Solution If we iterate over the input linked list and insert its value at the beginning of a new list the result would be a reversed linked list. Psuedo-code for the Brute Force Solution reversedLinkedList = LinkedList() temp = linked_list....

Problem Statement We have to implement the longestConsecutive function that takes an integer array as input and returns the length of the longest sequence of consecutive integers. For example, in array [4, 2, 7, 8, 1, 5, 6, 0] we have two sequences of consecutive integers: [0, 1, 2] and [4, 5, 6, 7, 8]. The longest sequence ([4, 5, 6, 7, 8]) has length 5. Brute Force Solution It would be easier to find consecutive sequences if the input array is sorted....

Problem Statement We have to implement an encode function that takes a list of string values as input and returns a single encoded string that could be transmitted over a network. On the other side of the network, the decode function will take the encoded string as input and return the original list of string values as output. A delimiter could be used to differentiate between words. For example, ["Hello", "World"] could be encoded with comma delimiter (,) to "Hello,World"....