root node of a tree, validate whether it is a valid Binary Search Tree. This is a tree where each node is unique, left children are smaller than the root and right children are greater than the root.
Given a string
s, return a
list containing of all possible partitions of that string that are palindromes. A palindrome is a string that is the same backwards as forwards. For example,
abba is a palindrome.
aab can be partitioned as follows:
[['a','a','b'], ['aa','b']]. This is because a single character is by definition a palindrome.
head of a linked list, remove all items with
val. Afterwards, return the new head.
Given an array
nums, delete all items that are equal to
val. Return the total number of remaining items and perform the deletion in place.
Traverse a tree where the
root node is given with a zig-zag level and return the values in a
list with one entry per level. For example: