I am getting the syntax error in the line mentioned - syntax

package conditionalStatements;
public class NestedIfElse {
public static void main(String[] args) {
int a = 12, b = 80 ,c = 50;
int result = 0;
if(a>b) {
if (a>c) {
result = a;
} else {
result = c;
}
} else {
if(b>c);{
result = b;
else { i am getting syntax error in this line
result = c;
}
}
}
System.out.println("largest of the the three numbers is " + result);
}
}
I am getting the syntax error in the line mentioned

public static void main(String[] args) {
int a = 12, b = 80 ,c = 50;
int result = 0;
if(a>b) {
if (a>c) {
result = a;
} else {
result = c;
}
} else {
if(b>c);{
result = b;
else { i am getting syntax error in this line
result = c;
}
}
}
System.out.println("largest of the the three numbers is " + result);
}
} // copy this one

public static void main(String[] args) {
int a = 12, b = 80 ,c = 50;
int result = 0;
if(a>b) {
if (a>c) {
result = a;
}
else {
result = c;
}
} else {
if(b>c){
result = b;
}else { // i am getting syntax error in this line
result = c;
}
}
System.out.println("largest of the the three numbers is " + result);
}

Related

how to change method signature from void to CompletionStage<Void>?

class AnotherClass {
Option<Integer> validateAndGetInt(Xyz xyz, Mno mno, String strValue) {
if (strValue != null) {
int intValue = 1;
try{
intValue = Integer.parseInt(strValue);
} catch (Exception e) {
throw new Exception("err");
}
Printer.getInstance().validateInt(xyz, mno, intValue);
return Optional.of(intValue);
}
}
} // class ends
class Printer {
void validateInt(Xyz xyz, Mno mno, int x) {
int m = xyz.getTeamVal(mno, x);
if(m < 0) {
throw new CustomException("invalid team value");
}
}
}
I am planning to move from void to CompletionStage<Void> for validate(int x).
validate will change as below, but I am not sure how to use in the calling side.
CompletionStage<Void> validateInt(Xyz xyz, Mno mno, int x) {
CompletableFuture<Void> f = new CompletableFuture<Void>();
int m = xyz.getTeamVal(mno, x);
if(m < 0) {
f.completeExceptionally(new CustomException("invalid team value"));
} else {
f.complete(null);
}
return f;
}
Can someone help explain how I can use it in AnotherClass?
I don't want to use this, as much as possible :
Printer.getInstance().validateInt(xyz, mno, intValue).toCompletableFuture().get()

Shortest uncommon subseqence

Given two strings s and t, determine length of shortest string z such that z is a subsequence of s and not a subsequence of t.
example :
s :babab,
t :babba
sol :
3 (aab)
not looking for copy pastable code, please if anybody can help with intution for solving this.
thanks a lot !
Here you go. I created on IEnumarable method which gives back all possible combinations. This is compared with t. I optimized the solution to loop only once over the not match String t.
using System;
using System.Collections.Generic;
namespace GuessTheNumber
{
public class Element:IComparable<Element>
{
public string Seq { get; set; }
public int Id { get; set; }
public int CompareTo(Element other)
{
return this.Seq.CompareTo(other.Seq);
}
}
class Program
{
static void Main(string[] args)
{
string s = "babab";
string t = "babba";
string z = ShortestUncommonSuqsequence(s, t);
}
static public string ShortestUncommonSuqsequence(string SubSequenceOf, string NotSubSequenceOf)
{
var uniqueSeq = new SortedList<Element, int>();
uniqueSeq.Add(new Element() { Seq = "", Id = -1 }, -1);
foreach (Element oneSequence in GetNextUniqueSequences(uniqueSeq, SubSequenceOf))
{
int index = oneSequence.Id + 1;
while (index < NotSubSequenceOf.Length)
{
char NotChar = NotSubSequenceOf[index];
if (oneSequence.Seq[oneSequence.Seq.Length - 1] == NotChar) break;
index++;
}
if (index == NotSubSequenceOf.Length)
{
return oneSequence.Seq;
}
else
{
oneSequence.Id = index;
}
}
return null;
}
static public IEnumerable<Element> GetNextUniqueSequences(SortedList<Element, int> UniqueSeq, string Input)
{
SortedList<Element, int> results = new SortedList<Element, int>();
foreach (var prevResult in UniqueSeq)
{
for (int i = 0; i < Input.Length; i++)
{
if (prevResult.Value < prevResult.Key.Seq.Length + i)
{
string nextStr = prevResult.Key.Seq + Input[i].ToString();
Element newElem = new Element() { Seq = nextStr, Id = prevResult.Key.Id };
if (!results.Keys.Contains(newElem))
{
results.Add(newElem, prevResult.Key.Seq.Length + i);
yield return newElem;
}
}
}
}
if (Input.Length > 1)
{
foreach (Element res in GetNextUniqueSequences(results, Input.Substring(1)))
{
yield return res;
}
}
}
}
}

heap data structure via pointers

Suggest an efficient way to find last position in heap satisfying the following conditions:
1) via pointers not via array
2) where we can insert or delete node
I could find it in O(n) time complexity but suggest a way which is of O(logn) or O(1) time complexity.
I'm assuming here that you mean a binary heap.
If you know how many nodes are in the heap, you can find the last node in O(log n) time by converting the count to binary, and then following the path of bits from high to low. That is, take the left node if the bit is 0, and the right node if the bit is 1.
For example, if there are three nodes in the heap, the binary representation of the count is 11. The root is always the first node, leaving you with 1. Then you take the right branch to get the last node.
Say there are 5 nodes in the heap:
1
2 3
4 5
In binary, that's 101. So you take the root. The next digit is 0 so you take the left branch. The next digit is 1, so you take the right branch, leaving you at node 5.
If you want the next available slot, you add 1 to the count and do the same thing. So 6 would be 110. You take the root, then the right branch, and the left child of 3 is where you'd add the new node.
You can do the same kind of thing with any d-ary heap, except that instead of converting to binary you convert to base d. So if your heap nodes each have up to three children, you'd convert the count to base 3, and use essentially the same logic as above.
An alternative is to maintain a reference to the last node in the heap, updating it every time you modify the heap. Or, if you want to know where the next node would be placed, you maintain a reference to the first node that doesn't have two children. That's O(1), but requires bookkeeping on every insertion or deletion.
I am answering my own question, There is no need to keep track of next pointer while inserting in heap (heap via pointers), even there is no need to keep track of parent, i am attaching running java code for heap, all possible method are included in it, getMin() = O(1), insert() = O(logn), extractMin = O(logn), decreasePriorityOfHead = O(logn), I have implemented it for generic code so it would be helpful to understand generic concept also.
class MinHeap<E extends Comparable<E>> {
private DoublyNode<E> root;
private int size = 0;
public DoublyNode<E> getRoot() {
return root;
}
public void setRoot(DoublyNode<E> root) {
this.root = root;
}
public int getSize() {
return size;
}
public void setSize(int size) {
this.size = size;
}
public MinHeap() {
}
public MinHeap(E data) {
this.root = new DoublyNode<E>(data);
this.size++;
}
private class NodeLevel<E extends Comparable<E>> {
private int level;
private DoublyNode<E> node;
public int getLevel() {
return level;
}
public void setLevel(int level) {
this.level = level;
}
public DoublyNode<E> getNode() {
return node;
}
public void setNode(DoublyNode<E> node) {
this.node = node;
}
public NodeLevel(DoublyNode<E> node, int level) {
this.node = node;
this.level = level;
}
}
public void insert(E data) {
if (this.size == 0) {
this.root = new DoublyNode<E>(data);
this.size++;
return;
}
DoublyNode<E> tempRoot = this.root;
Integer insertingElementPosition = this.size + 1;
char[] insertingElementArray = Integer.toBinaryString(
insertingElementPosition).toCharArray();
DoublyNode<E> newNode = new DoublyNode<E>(data);
int i;
for (i = 1; i < insertingElementArray.length - 1; i++) {
if (newNode.getData().compareTo(tempRoot.getData()) < 0) {
this.swap(newNode, tempRoot);
}
char c = insertingElementArray[i];
if (c == '0') {
tempRoot = tempRoot.getLeft();
} else {
tempRoot = tempRoot.getRight();
}
}
// newNode.setParent(tempRoot);
if (newNode.getData().compareTo(tempRoot.getData()) < 0) {
this.swap(newNode, tempRoot);
}
if (insertingElementArray[i] == '0') {
tempRoot.setLeft(newNode);
} else {
tempRoot.setRight(newNode);
}
this.size++;
}
public void swap(DoublyNode<E> node1, DoublyNode<E> node2) {
E temp = node1.getData();
node1.setData(node2.getData());
node2.setData(temp);
}
public E getMin() {
if (this.size == 0) {
return null;
}
return this.root.getData();
}
public void heapifyDownWord(DoublyNode<E> temp) {
if (temp == null) {
return;
}
DoublyNode<E> smallerChild = this.getSmallerChild(temp);
if (smallerChild == null) {
return;
}
if (smallerChild.getData().compareTo(temp.getData()) < 0) {
this.swap(temp, smallerChild);
this.heapifyDownWord(smallerChild);
}
}
public DoublyNode<E> getSmallerChild(DoublyNode<E> temp) {
if (temp.getLeft() != null && temp.getRight() != null) {
return (temp.getLeft().getData()
.compareTo(temp.getRight().getData()) < 0) ? temp.getLeft()
: temp.getRight();
} else if (temp.getLeft() != null) {
return temp.getLeft();
} else {
return temp.getRight();
}
}
public E extractMin() {
if (this.root == null) {
return null;
}
E temp = this.root.getData();
if (this.root.getLeft() == null && this.root.getRight() == null) {
this.root = null;
this.size--;
return temp;
}
DoublyNode<E> parentOfLastData = this.getParentOfLastData();
if (parentOfLastData.getRight() != null) {
this.root.setData(parentOfLastData.getRight().getData());
parentOfLastData.setRight(null);
} else {
this.root.setData(parentOfLastData.getLeft().getData());
parentOfLastData.setLeft(null);
}
this.heapifyDownWord(this.root);
return temp;
}
public DoublyNode<E> getParentOfLastData() {
if (this.size == 0) {
return null;
}
DoublyNode<E> tempRoot = this.root;
Integer insertingElementPosition = this.size;
char[] insertingElementArray = Integer.toBinaryString(
insertingElementPosition).toCharArray();
int i;
for (i = 1; i < insertingElementArray.length - 1; i++) {
char c = insertingElementArray[i];
if (c == '0') {
tempRoot = tempRoot.getLeft();
} else {
tempRoot = tempRoot.getRight();
}
}
return tempRoot;
}
public DoublyNode<E> getParentOfLastEmptyPosition() {
if (this.size == 0) {
return null;
}
DoublyNode<E> tempRoot = this.root;
Integer insertingElementPosition = this.size + 1;
char[] insertingElementArray = Integer.toBinaryString(
insertingElementPosition).toCharArray();
System.out.println(insertingElementArray.toString());
int i;
for (i = 1; i < insertingElementArray.length - 1; i++) {
char c = insertingElementArray[i];
if (c == '0') {
tempRoot = tempRoot.getLeft();
} else {
tempRoot = tempRoot.getRight();
}
}
return tempRoot;
}
public void print() {
if (this.root == null) {
System.out.println("Heap via pointer is empty!");
return;
}
System.out.println("\n Heap via pointer is:- ");
Queue<NodeLevel<E>> dataQueue = new Queue<NodeLevel<E>>();
Queue<Space> spaceQueue = new Queue<Space>();
dataQueue.enQueue(new NodeLevel<E>(this.root, 1));
int heightOfTree = this.getHeightOfHeap();
Double powerHeghtBST = Math.pow(heightOfTree, 2);
spaceQueue.enQueue(new Space(powerHeghtBST.intValue(), false));
while (!dataQueue.isEmpty()) {
Space space = spaceQueue.deQueue();
NodeLevel<E> nodeLevel = dataQueue.deQueue();
while (space.isNullSpace()) {
space.printNullSpace();
spaceQueue.enQueue(space);
space = spaceQueue.deQueue();
}
space.printFrontSpace();
System.out.print(nodeLevel.getNode().getData().printingData());
space.printBackSpace();
if (nodeLevel.getNode().getLeft() != null) {
dataQueue.enQueue(new NodeLevel<E>(nodeLevel.getNode()
.getLeft(), nodeLevel.getLevel() + 1));
spaceQueue.enQueue(new Space(space.getSpaceSize() / 2, false));
} else {
spaceQueue.enQueue(new Space(space.getSpaceSize() / 2, true));
}
if (nodeLevel.getNode().getRight() != null) {
dataQueue.enQueue(new NodeLevel<E>(nodeLevel.getNode()
.getRight(), nodeLevel.getLevel() + 1));
spaceQueue.enQueue(new Space(space.getSpaceSize() / 2, false));
} else {
spaceQueue.enQueue(new Space(space.getSpaceSize() / 2, true));
}
if (!dataQueue.isEmpty()
&& nodeLevel.getLevel() + 1 == dataQueue.getFrontData()
.getLevel()) {
System.out.println("\n");
}
}
}
public int getHeightOfHeap() {
if (this.size == 0) {
return 0;
}
Double height = Math.log(this.size) / Math.log(2) + 1;
return height.intValue();
}
public void changePriorityOfHeapTop(E data) {
if (this.root == null) {
return;
}
this.root.setData(data);
this.heapifyDownWord(this.root);
}
}
interface Comparable<T> extends java.lang.Comparable<T> {
/**
* this methos returns a string of that data which to be shown during
* printing tree
*
* #return
*/
public String printingData();
}
public class PracticeMainClass {
public static void main(String[] args) {
MinHeap<Student> minHeap1 = new MinHeap<Student>();
minHeap1.insert(new Student(50, "a"));
minHeap1.insert(new Student(20, "a"));
minHeap1.insert(new Student(60, "a"));
minHeap1.insert(new Student(30, "a"));
minHeap1.insert(new Student(40, "a"));
minHeap1.insert(new Student(70, "a"));
minHeap1.insert(new Student(10, "a"));
minHeap1.insert(new Student(55, "a"));
minHeap1.insert(new Student(35, "a"));
minHeap1.insert(new Student(45, "a"));
minHeap1.print();
minHeap1.getMin();
minHeap1.print();
System.out
.println("\nminimum is:- " + minHeap1.getMin().printingData());
minHeap1.print();
System.out.println("\nminimum is:- "
+ minHeap1.extractMin().printingData());
minHeap1.print();
minHeap1.changePriorityOfHeapTop(new Student(75, "a"));
minHeap1.print();
}
}
class DoublyNode<E extends Comparable<E>> {
private E data;
private DoublyNode<E> left;
private DoublyNode<E> right;
// private DoublyNode<E> parent;
public DoublyNode() {
}
public DoublyNode(E data) {
this.data = data;
}
public E getData() {
return data;
}
public void setData(E data) {
this.data = data;
}
public DoublyNode<E> getLeft() {
return left;
}
public void setLeft(DoublyNode<E> left) {
this.left = left;
}
public DoublyNode<E> getRight() {
return right;
}
public void setRight(DoublyNode<E> right) {
this.right = right;
}
// public DoublyNode<E> getParent() {
// return parent;
// }
// public void setParent(DoublyNode<E> parent) {
// this.parent = parent;
// }
}
class Space {
private boolean isNullSpace = false;
private String frontSpace;
private String backSpace;
private String nullSpace;
private int spaceSize;
public boolean isNullSpace() {
return isNullSpace;
}
public void setNullSpace(boolean isNullSpace) {
this.isNullSpace = isNullSpace;
}
public int getSpaceSize() {
return spaceSize;
}
public void setSpaceSize(int spaceSize) {
this.spaceSize = spaceSize;
}
public Space(int spaceSize, boolean isNullSpace) {
this.isNullSpace = isNullSpace;
this.spaceSize = spaceSize;
if (spaceSize == 0) {
this.frontSpace = "";
this.backSpace = "";
this.nullSpace = " ";
} else if (spaceSize == 1) {
this.frontSpace = " ";
this.backSpace = "";
this.nullSpace = " ";
} else if (spaceSize == 2) {
this.frontSpace = " ";
this.backSpace = "";
this.nullSpace = " ";
} else {
this.frontSpace = String.format("%" + (spaceSize) + "s", " ");
this.backSpace = String.format("%" + (spaceSize - 2) + "s", " ");
this.nullSpace = String.format("%" + 2 * (spaceSize) + "s", " ");
}
}
public void printFrontSpace() {
System.out.print(this.frontSpace);
}
public void printBackSpace() {
System.out.print(this.backSpace);
}
public void printNullSpace() {
System.out.print(this.nullSpace);
}
}
class Queue<E> {
private Node<E> front;
private Node<E> rear;
private int queueSize = 0;
public Queue() {
}
public Queue(E data) {
this.front = new Node(data);
this.rear = this.front;
}
public void enQueue(E data) {
if (this.rear == null) {
this.rear = new Node(data);
this.front = this.rear;
} else {
Node newNode = new Node(data);
this.rear.setNext(newNode);
this.rear = newNode;
}
this.queueSize++;
}
public E deQueue() {
E returnValue;
if (this.front == null) {
return null;
} else if (this.front == this.rear) {
returnValue = this.front.getData();
this.front = null;
this.rear = null;
} else {
returnValue = this.front.getData();
this.front = this.front.getNext();
}
this.queueSize--;
return returnValue;
}
public void print() {
Node temp = this.front;
System.out.print("\n Queue is:- ");
if (temp == null) {
System.out.println(" Empty! ");
}
while (temp != null) {
System.out.print(temp.getData() + ",");
temp = temp.getNext();
}
}
public int getQueueSize() {
return queueSize;
}
public E getFrontData() {
if (this.front == null) {
System.out.println("queue is empty!");
return null;
}
return this.front.getData();
}
public E getRearData() {
if (this.rear == null) {
System.out.println("queue is empty!");
return null;
}
return this.rear.getData();
}
public boolean isEmpty() {
return this.front == null;
}
}
class Node<E> {
private E data;
private Node next;
public Node(E data) {
this.data = data;
}
public E getData() {
return data;
}
public void setData(E data) {
this.data = data;
}
public Node getNext() {
return next;
}
public void setNext(Node next) {
this.next = next;
}
}
class Student implements Comparable<Student> {
private int id;
private String name;
#Override
public int compareTo(Student student) {
if (this.id == student.id) {
return 0;
} else if (this.id < student.id) {
return -1;
} else {
return 1;
}
}
public Student(int id, String name) {
this.id = id;
this.name = name;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
#Override
public String printingData() {
// String printingData = "{ id: "+this.id+" name: "+this.name+" }";
String printingData = String.valueOf(this.id);
return printingData;
}
}
Output of this code is:-
Heap via pointer is:-
10
30 20
35 40 70 60
55 50 45
Heap via pointer is:-
10
30 20
35 40 70 60
55 50 45
minimum is:- 10
Heap via pointer is:-
10
30 20
35 40 70 60
55 50 45
minimum is:- 10
Heap via pointer is:-
20
30 45
35 40 70 60
55 50
Heap via pointer is:-
30
35 45
50 40 70 60
55 75

Null pointer Exception while reversing a Queue using stack

I was practicing on how to implement queue using arrays. I have easily implemented how to enqueue and dequeue the elements in queue. But I have encountered an exception while implementing reverse of queue using stacks
public class QueueImpl {
private int capacity;
int queueArr[];
int front = 0;
int rear = -1;
int currentSize = 0;
QueueImpl(int queueSize){
this.capacity=queueSize;
queueArr=new int[this.capacity];
}
public void enqueue(int data){
if(isQueueFull()){
System.out.println("Overflow");
return;
}
else{
rear=rear+1;
if(rear==capacity-1)
{
rear=0;
}
queueArr[rear]=data;
currentSize++;
System.out.println("Element " + data+ " is pushed to Queue !");
}
}
public int dequeue(){
if(isQueueEmpty()){
System.out.println("UnderFlow");
}
else{
front=front+1;
if(front == capacity-1){
System.out.println("Pop operation done ! removed: "+queueArr[front-1]);
front = 0;
} else {
System.out.println("Pop operation done ! removed: "+queueArr[front-1]);
}
currentSize--;
}
return queueArr[front-1];
}
private boolean isQueueEmpty() {
boolean status=false;
if(currentSize==0){
status=true;
}
return status;
}
private boolean isQueueFull() {
boolean status=false;
if(currentSize==capacity){
status=true;
}
return status;
}
public static void main(String arg[]) {
QueueImpl queueImpl=new QueueImpl(5);
queueImpl.enqueue(5);
queueImpl.enqueue(2);
queueImpl.enqueue(9);
queueImpl.enqueue(1);
// queueImpl.dequeue();
queueImpl.printQueue(queueImpl);
queueImpl.reverse(queueImpl);
}
private void printQueue(QueueImpl queueImpl) {
System.out.println(queueImpl.toString());
}
#Override
public String toString() {
return "Queue [front=" + front + ", rear=" + rear + ", size=" + currentSize
+ ", queue=" + Arrays.toString(queueArr) + "]";
}
private QueueImpl reverse(QueueImpl queueImpl) throws ArrayIndexOutOfBoundsException {
int i=0;
Stack<Integer> stack=new Stack<Integer>();
while(!queueImpl.isQueueEmpty()){
stack.push(queueImpl.dequeue());
}
while(!stack.isEmpty()){
stack.get(i);
i++;
}
while(!stack.isEmpty()){
queueImpl.enqueue(stack.pop());
}
return queueImpl;
}
}
The error log is -
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -1
at com.tcs.QueueUsingAraay.QueueImpl.dequeue(QueueImpl.java:51)
at com.tcs.QueueUsingAraay.QueueImpl.reverse(QueueImpl.java:93)
at com.tcs.QueueUsingAraay.QueueImpl.main(QueueImpl.java:78)
There was a problem in your dequeue method:
1. you were making front=0 and were trying to access front-1 which was -1
as a result the exception was thrown.
Removed stack.get as it was not required.
Corrected working code.
public class QueueImpl {
private int capacity;
int queueArr[];
int front = 0;
int rear = -1;
int currentSize = 0;
QueueImpl(int queueSize) {
this.capacity = queueSize;
queueArr = new int[this.capacity];
}
public void enqueue(int data) {
if (isQueueFull()) {
System.out.println("Overflow");
return;
} else {
rear = rear + 1;
if (rear == capacity - 1) {
rear = 0;
}
queueArr[rear] = data;
currentSize++;
System.out.println("Element " + data + " is pushed to Queue !");
}
}
public int dequeue() {
int element=-1;
if (isQueueEmpty()) {
System.out.println("UnderFlow");
} else {
element = queueArr[front];
front=front+1;
if (front == capacity - 1) {
System.out.println("Pop operation done ! removed: "
+ queueArr[front - 1]);
front = 0;
} else {
System.out.println("Pop operation done ! removed: "
+ queueArr[front - 1]);
}
currentSize--;
}
return element;
}
private boolean isQueueEmpty() {
boolean status = false;
if (currentSize == 0) {
status = true;
}
return status;
}
private boolean isQueueFull() {
boolean status = false;
if (currentSize == capacity) {
status = true;
}
return status;
}
public static void main(String arg[]) {
QueueImpl queueImpl = new QueueImpl(5);
queueImpl.enqueue(5);
queueImpl.enqueue(2);
queueImpl.enqueue(9);
queueImpl.enqueue(1);
queueImpl.printQueue(queueImpl);
queueImpl.reverse(queueImpl);
queueImpl.printQueue(queueImpl);
}
private void printQueue(QueueImpl queueImpl) {
System.out.println(queueImpl.toString());
}
#Override
public String toString() {
return "Queue [front=" + front + ", rear=" + rear + ", size="
+ currentSize + ", queue=" + Arrays.toString(queueArr) + "]";
}
private QueueImpl reverse(QueueImpl queueImpl)
throws ArrayIndexOutOfBoundsException {
Stack<Integer> stack = new Stack<Integer>();
while (!queueImpl.isQueueEmpty()) {
stack.push(queueImpl.dequeue());
}
while (!stack.isEmpty()) {
queueImpl.enqueue(stack.pop());
}
return queueImpl;
}
}

To check an input string is present in custom table of strings

Assume length of element in table is 1 or 2.
Table: { h, fe, na, o}
input string: nafeo
Output: true
Table: {ab,bc}
input string: abc
Output: false
Please advise my below code will cover all the cases and is this the best solution? Or am I missing anything, any alternate solutions?
import java.util.*;
public class CustomTable {
Set<String> table = new HashSet<String>();
public CustomTable(){
// add your elements here for more test cases
table.add("oh");
table.add("he");
}
public int checkTable( String prev, String curr, String next) {
System.out.print(prev+":"+curr+":"+next);
System.out.println();
if (prev!=null) if (table.contains(prev)) return -1;
if (table.contains(curr)) return 0;
if (table.contains(next)) return 1;
return 2;
}
// ohhe.
public static void main(String args[]) {
CustomTable obj = new CustomTable();
String inputStr = "ohheo"; //Tested ohe,ohhe,ohohe
int result = 0;
String curr, prev, next;
for (int i = 0; i < inputStr.length(); i++) {
// if prev element is found
if (result==-1){
prev = null;
}
else {
if (i > 0) {
prev = inputStr.substring(i - 1, i + 1);
} else {
prev = inputStr.substring(i, i + 1);
}
}
curr = inputStr.substring(i,i+1);
if (i < inputStr.length()-1) {
next = inputStr.substring(i, i+2);
} else {
next = inputStr.substring(i, i+1);
}
result = obj.checkTable(prev, curr, next);
if (result==2) {
System.out.print("false");
return;
}
}
System.out.print("true");
}
}
I think the problem have similarities to well known subset sum problem and you can use its solutions by some customization.

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