Coding Puzzles

Floyd Triangle

Problem

Floyd Triangle

Solution

Floyd Triangle

Note- Floyd Triangle is like
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An algorithm which creates a linked list of all the nodes at each depth of a Binary Tree

Problem

Given a binary tree, design an algorithm which creates a linked list of all the nodes at each depth (e.g., if you have a tree with depth D…

Print Prime numbers in Java

Problem

How to print Prime numbers in Java or how to check if a number is prime or not?

Solution

Here is complete sample code example to print prime numbers from 1 to any specified number.…

Given a directed graph, design an algorithm to find out whether there is a route between two nodes.

Problem

Given a directed graph, design an algorithm to find out whether there is a route between two nodes.

Replace all spaces in a string with ‘%20’

Problem

Write a method to replace all spaces in a string with ‘%20’. You may assume that the string has sufficient space at the end of the string to hold the additional characters, and that you are given the “true” length of…

Factorial of a number in Java

Problem

How to find factorial of a number in Java on both recursive and iterative way?

Solution

If you look at closely you will find that recursive solution of calculating factorial is much…

Insertion Sort in Java

Write code to implement Insertion Sort in Java

Solution

In this Java program, we will sort an integer array using Insertion sort algorithm in Java. Insertion sort should only be used with small arrays or linked lists. We are going…

Check if an integer number is power of two

Problem

How to check if an integer number is power of two?

Solution

3 simple examples to check if any integer number is power of 2 or not.
We have three methods, which…

Fibonacci series in Java by using recursion or for loop

Problem

Printing Fibonacci series in Java by using recursion or for loop

Solution

import java.util.Arrays; 
import java.util.Scanner; 
/** 
* Java…

Finds if a number is a palindrome or not

Problem

Java program which finds if a number is a palindrome or not

Solution

This program does not use any API method instead it uses division and
remainder operator of…

Reverse a null terminated string in C or C++

Problem

Implement a function void reverse(char* str) in C or C++ which reverses a null-terminated string.

Solution

Determine if a string has all unique characters.

Problem

Implement an algorithm to determine if a string has all unique characters. What if you cannot use additional data structures?

Solution

Verify if a number is Even/Odd in Java

Problem

Verify if a number is Even/Odd in Java

Solution

public class EvenOdd{
   public static void main(String[] args){
      Scanner in = new Scanner(System.in);
    …

Algorithm to find the Kth to last element of a singly linked list

Problem

Implement an algorithm to find the kth to last element of a singly linked list using an iterative solution

Solution

Implement a function to check if a binary tree is balanced

Problem

Implement a function to check if a binary tree is balanced. For the purposes of this question, a balanced tree is defined to be a tree such that the heights of the two subtrees of any node…

Longest Palindromic Substring in Java

Problem

Longest Palindromic Substring

Solution

Time O(n^2), Space O(1)

public String longestPalindrome(String s) {
   if (s.isEmpty()) {
      return…

Swap Two Numbers Without Using Third Variable in Java

Problem

Java Program on Swapping Two Numbers Without Using Third Variable
using Bitwise Operators and Multiplication & Division

Solution

Determine if a String is a Substring in C++

Problem

Write a program to determine whether an input string x is a substring of another input string y. (For example, “bat” is a substring of “abate”, but not of “beat”.)

Solution

Find smallest and largest number from an array

Problem

Example of Java program to find smallest and largest number from an integer array

Solution

Remove any given character from a String

Problem

Remove any given character from a String

Solution

/**
 * Removes any given character from a String.<br>
 * This program uses the StringBuilder to avoid un…