Find all employees who directly or indirectly reports to a manager
Given a map containing employee to manager mappings, find all employees under each manager who directly or indirectly reports him.
Tag: Hashing
Find postorder traversal of a binary tree from its inorder and preorder sequence
Write an efficient algorithm to find postorder traversal on a given binary tree from its inorder and preorder sequence.
Find subarrays with a given sum in an array
Given an integer array, find subarrays with a given sum in it.
Iteratively print the leaf to root path for every leaf node in a binary tree
Given a binary tree, write an iterative algorithm to print the leaf-to-root path for every leaf node. Use of recursion is prohibited.
Find a pair with the given sum in a BST
Given a binary search tree, find a pair with a given sum present in it.
Compute the maximum number of nodes at any level in a binary tree
Given a binary tree, write an efficient algorithm to compute the maximum number of nodes in any level in the binary tree.
3–Partition Problem
Given a set S of positive integers, determine if it can be partitioned into three disjoint subsets that all have the same sum, and they cover S.
Build a binary tree from a parent array
Given 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.
Find two odd occurring elements in an array without using any extra space
Given an integer array, duplicates appear in it an even number of times except for two elements, which appear an odd number of times. Find both odd appearing elements without using any extra memory.
Find pairs with difference `k` in an array | Constant Space Solution
Given an unsorted integer array, find all pairs with a given difference k in it without using any extra space.
Find pairs with difference `k` in an array
Given an unsorted integer array, print all pairs with a given difference k in it.
Find the frequency of each element in a sorted array containing duplicates
Given a sorted array containing duplicates, efficiently find each element’s frequency without traversing the whole array.