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Get StartedGiven a string and a pattern containing wildcard characters, i.e., * and ?’, where ? can match to any single character in the string and * can match to any number of characters including zero characters, design an efficient algorithm to find if the pattern matches with the complete string or not.
The Longest Increasing Subsequence (LIS) problem is to find a subsequence of a given sequence in which the subsequence’s elements are in sorted order, lowest to highest, and in which the subsequence is as long as possible. This subsequence is not necessarily contiguous or unique.
Given an integer array, find the maximum product subarray. In other words, find a subarray that has the maximum product of its elements.
Trapping rainwater problem: Find the maximum amount of water that can be trapped within a given set of bars where each bar’s width is 1 unit.
Generate all permutations of a string in Java.
Given a sequence consisting of I and D, where I denotes the increasing sequence and D denotes the decreasing sequence, decode the sequence to construct a minimum number without repeated digits.
Given a circular integer array, find a subarray with the largest sum in it.
Given a binary array, find the index of 0 to be replaced with 1 to get the maximum length sequence of continuous ones.
Given two arrays that represent a set of BST keys, check if they represent the same BSTs or not. We are not allowed to build the tree.
Given a binary tree containing many zero nodes, sink nodes having zero value at the bottom of the subtree rooted at that node. In other words, the output binary tree should not contain any node having zero value that is the parent of the node having a non-zero value.
Given a binary tree, in-place convert it into a doubly linked list. The left and right pointers of binary tree nodes should act as previous and next pointers in a doubly-linked list, and the doubly linked list nodes should follow the same order of nodes as inorder traversal on the tree.
Given a binary tree, the print vertical sum of it. Assume the left and right child of a node makes a 45–degree angle with the parent.