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Get StartedGiven an array representing a binary tree, such that the parent-child relationship is defined by (A[i], i) for every index i in array A, build a binary tree out of it. The root node’s value is i if -1 is present at index i in the array.
Given an unsorted integer array of size n, whose elements lie in the range 0 to n-1, rearrange the array such that A[A[i]] is set to i for every array element A[i].
Given a linear equation of k variables, count the total number of possible solutions to it. The problem is similar to finding the total number of ways to get the denomination of coins. Here, coefficients of an equation can be considered coins denominations, and the RHS of an equation can be considered the desired change.
The longest decreasing subsequence problem is to find a subsequence of a given sequence in which the subsequence’s elements are in sorted order, highest to lowest, and in which the subsequence is as long as possible. This subsequence is not necessarily contiguous or unique.
Given a list containing future predictions of share prices, find the maximum profit earned by buying and selling shares at most twice with a constraint that a new transaction can only start after the previous transaction complete, i.e., we can only hold at most one share at a time.
Given a list containing future predictions of share prices, find the maximum profit earned by buying and selling shares at most k times with a constraint that a new transaction can only start after the previous transaction is complete, i.e., we can only hold at most one share at a time.
Find all n–digit numbers with an equal sum where n varies from 1 to 9 and sum <= 81 (Maximum possible sum in a 9–digit number).
Given a maze in the form of a rectangular matrix, filled with either O, X, or M, where O represents an open cell, X represents a blocked cell, and M represents landmines in the maze, find the shortest distance of every open cell in the maze from its nearest mine.
Given an integer array having distinct elements, find the surpasser count for each element in it. In other words, for each array element, find the total number of elements to its right, which are greater than it.
Given M sorted lists of variable length, print them efficiently in sorted order.
Introsort is an efficient in-place sorting algorithm, which usually beats all other sorting algorithms in terms of performance. Due to its high performance, it is used in several standard library sort functions.
Given a string, calculate its rank among all its lexicographically sorted permutations.