shaaslam

public static String rotate(String string, int k){
        if(string == null) return string;
        if(string.length() < 2) return string;
        if(k > string.length()) k = k % string.length();

        char[] result = new char[string.length()];

        for(int i = 0; i < k; i++){
            result[i] = string.charAt(string.length() - k + i);
        }

shaaslam

package com.shaaslam.tiny;

import java.time.LocalDateTime;
import java.time.ZoneId;

public class TinyUtils {
	
	private static final String ALPHABET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
	private static final long BASE = ALPHABET.length();
	

shaaslam

import java.util.Arrays;

public class Subsets {

	public static void main(String[] args) {
		String array[] = {"a", "b", "c"};
		System.out.println(Arrays.deepToString(subset(array)));
	}
	
	public static String[] subset(String array[]) {

shaaslam

public class DoublePower {

	public static void main(String[] args) {
		double d = 5;
		int n = 2;
		System.out.println(pow(d,n));
	}
	
	public static double pow(double d, int e) {
		if(e == 0) return 1; // base case --> if exponent is zero, answer is 1

shaaslam

public class isBST {

	public static void main(String[] args) {
		int array[] = {30, 85, 5};
		Arrays.sort(array);
		TreeNode node = TreeNode.createMinimalBST(array);
		node.print();
		System.out.println(node.isBST());
		System.out.println(isValidBST(node));

shaaslam

package tree;

import java.util.ArrayList;
import java.util.Arrays;

public class PrintAllPaths {

	public static void main(String[] args) {
		int array[] = {30,	20,	54,	85, 10,	46,	5,	13,	26};
		Arrays.sort(array);

shaaslam

/*
 * 	Let T be a rooted tree. The lowest common ancestor between two nodes n1 and n2 is defined
	as the lowest node in T that has both n1 and n2 as descendants.
	The LCA of n1 and n2 in T is the shared ancestor of n1 and n2 that is located farthest from the
	root. Computation of lowest common ancestors may be useful, for instance, as part of a
	procedure for determining the distance between pairs of nodes in a tree: the distance from n1
	to n2 can be computed as the distance from the root to n1, plus the distance from the root to
	n2, minus twice the distance from the root to their lowest common ancestor. (Source: Wikipedia)
	Design an write an algorithm to find the LCA node, given two nodes in a Binary Tree.

shaaslam

public class Flip {

	public static void main(String[] args) {
		int array[] = {1,2,3,4,5,6,7};
		TreeNode node = TreeNode.createMinimalBST(array);
		node.print();
		flip(node);
		node.print();
	}

shaaslam

import java.util.HashMap;

public class PhoneDialer {
	public static HashMap<String, String> map = new HashMap<>();
	
	static {
		map.put("0", "0");
		map.put("1", "1");
		map.put("2", "ABC");
		map.put("3", "DEF");

shaaslam

import java.util.Arrays;

public class Successor {
	
	public static void main(String[] args) {
		int array[] = {30,	20,	54,	85, 10,	46,	5,	13,	26};
		Arrays.sort(array);
		TreeNode node = TreeNode.createMinimalBST(array);
		node.print();