Objective: Reverse the given linked list.
Input: A Linked List
Output: Reversed Linked List
Example:
Input : ->30->25->20->15->10->5 Reversed : ->5->10->15->20->25->30
NOTE : Click Reverse a Linked List – Part 2 to see the another implementation of this problem.
Approach:
Linked List- As the name suggests it’s a list which is linked.
Nodes are nothing but objects of a class and each node has data and a link to the next node.
class Node { public int data; public Node next; public Node(int data) { this.data = data; this.next = null; } }
Objective: Write an algorithm to find out whether in a given array there exists or not two numbers whose sum is exactly equals to a given number. This problem has been asked in Amazon and Microsoft interviews.
Input: An array arrA[], A number k
Output: True or false based upon we have found any two numbers in array arrA[] whose sum is equal to k
Approach:
Method 1: Using Binary Search
Read moreFind a pair of numbers from an array whose sum equals k
Objective: Write an algorithm to find out whether in a given string contains all the unique characters. This question has been asked in the Amazon and Microsoft interviews.
Input: A String
Output: True or false based upon whether string contains all the unique characters or not.
Approach:
Method 1.
Objective : Write an algorithm to find Whether Given String is palindrome or Not.
Input: A String,
Output: true or false on whether string is palindrome or not
Approach:
Example:
Jain niaJ => compare ‘J’ with ‘J’ =>returns true ain nia => compare ‘a’ with ‘a’ =>returns true in ni => compare ‘i’ with ‘i’ =>returns true n n => compare ‘n’ with ‘n’ =>returns true string length <2 => returns true
Objective : In this article we will discuss an algorithm to Find a peak element in a Given Array. We will see the recursion techniques to solve this problem.
Peak Element: peak element is the element which is greater than or equal to both of its neighbors.
Input: Array, arrA[] .
Output: A peak element and its index
Approach:
A simple approach is to do a linear scan to a array and using few variables we can find a peak element. But the Time Complexity will be O(n) but real question is, Can we do better?
The Answer is yes, by using Binary Search techniques.
Objective : Write an algorithm to find two Missing Numbers in a Sequence of Consecutive Numbers
Input: Array, arrA[] with two missing numbers and Range
Output : Two missing numbers
Approach:
Read moreFind two Missing Numbers in a Sequence of Consecutive Numbers
Objective : You have been asked to Write an algorithm Find a Missing Number From a Sequence of Consecutive Numbers
Input: Array, arrA[] with a missing number and Range
Output : missing number
Approach:
Read moreFind a Missing Number From a Sequence of Consecutive Numbers
Objective : To implement a Hash Table
Input: A set of pairs of keys and values
Approach:
Objective : Write an algorithm to find an element in an sorted array Input: A sorted array, arrA[] and an key Output : Return true if element is found, else false. Approach: The idea is to compare the middle element of array with the key, if key equal to the middle element , that’s it … Read more Binary Search