Find the minimum index of a repeating element in an array
Given an integer array, find the minimum index of a repeating element in linear time and doing just one traversal of the array.
Tag: Easy
Find a pair with a minimum absolute sum in an array
Given a sorted integer array, find a pair in it having an absolute minimum sum.
Clone a Binary Tree
Given a binary tree, efficiently clone of it.
Merge two sorted arrays from their end
Given two sorted integer arrays, merge them into a single array in decreasing order, and return it. In other words, merge two sorted arrays from their end.
Merge two sorted arrays
Given two integer arrays, each of which is sorted in increasing order, merge them into a single array in increasing order, and return it.
Find an index of the maximum occurring element with equal probability
Given an integer array, find the index of the maximum occurring element with an equal probability.
Count all paths in a matrix from the first cell to the last cell
Given an M × N rectangular grid, efficiently count all paths starting from the first cell (0, 0) to the last cell (M-1, N-1). We can either move down or move towards right from a cell.
Find the square root of a number using a binary search
Given a positive number, find the square root of it. If the number is not a perfect square, then return the floor of its square root.
Unbounded Binary Search
Given a monotonically increasing function f(x) on the non-negative integers, find the value of x, where f(x) becomes positive for the first time. In other words, find a positive integer x such that f(x-1), f(x-2), … are negative and f(x+1), f(x+2), … are positive.
Longest Common Prefix (LCP) Problem
Write an efficient algorithm to find the longest common prefix (LCP) between a given set of strings.
Reverse an array in C++
This post will discuss how to reverse an array in C++.
Construct an ancestor matrix from a binary tree
Given a binary tree whose nodes are labeled from 0 to N-1, construct an N × N ancestor matrix. An ancestor matrix is a boolean matrix, whose cell (i, j) is true if i is an ancestor of j in the binary tree.