Implement a Queue by using two Stacks

Problem Implement a MyQueue class which implements a queue using two stacks Source Code

Sort an array of strings by anagrams

Problem Write a method to sort an array of strings so that all the anagrams are next to each other. Solution This problem asks us to group the strings in arrays such that anagrams appear next to each other. How to find the anagram The feat…

Merge two sorted arrays

Problem You are given two sorted arrays, A and B, where A has large enough buffer at the end to hold B. Write a method to merge B into A in sorted order How to Solve By merging two arrays like merge sort, we can achieve the goal. Since A h…

Merge Sort and Quick Sort

Merge Sort Runtime: 0(n Log(n)) average and worst case. Quick Sort Runtime: 0(n Log(n)) average,0(n2) worst case.

Write a method to return all subsets of a set

Problem Write a method to return all subsets of a set Solution This problem can be solve by choosing each element or not. For example we given an array = {1, 2, 3}. First, we do the two patterns that we select 1 or not. By this operation, …

Find a Magic Index from Sorted Array

Problem A magic index in an array A[] is defined to be an index such that A[i] = i. Given a sorted array of distinct integers, write a method to find a magic index, if one exists, in array A. FOLLOW UP What if the values are not distinct? …