Segment Tree
Segment tree is a data structure that is used to solve a certain problem, called RMQ (Range Minimum Query).
Author: Logan
How to find all pairs of integers in an array that have the same product?
The goal is to find all the pairs from the given vector arr which have the product p. We could solve this problem in O(n).
How to find k nearest neighbours of a given point from a set of points in a plane?
Let’s given n points in a plane. We’ve to find k nearest neighbours of a given point ‘p’ from the given n points.
Sieve of Eratosthenes | HackerRank Solution
The sieve of Eratosthenes is an ancient algorithm for finding all prime numbers up to any given limit. It does so by iteratively marking numbers in the range as composite by marking the multiples of each prime as non-prime.
Activity Selection problem
Activity selection problem is the problem of selecting the largest set of mutually exclusive activities. Each activity has its own starting time si and finish time fi. No two activities can share the resource at any time point.
Custom Sort String – LeetCode Solution [Medium]
You are given two strings order and t. All the words of order are unique and were sorted in some custom order previously.
Job sequencing problem
There are n jobs to be processed on a machine. Each job i has a deadline and a profit. Profit is earned if the job is completed by its deadline. Job is completed if it is processed on a machine for unit time.
Decode Ways – LeetCode Solution [Medium]
A message containing letters from A-Z can be encoded into numbers. To decode an encoded message, all the digits must be grouped then mapped back into letters using the reverse of the mapping
Greedy approach vs Dynamic Programming
Greedy approach and Dynamic programming both are used for solving optimisation problems. However often we need to use DP since optimal solution cannot be guaranteed by a greedy algorithm.
Knapsack problem (Finding selected items)
A little recap: Let given weights & values of n items to be put in a knapsack of capacity W ie.