using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;
namespace MaxCommonArraySlice
{
class Program
{
public static int maxCommonArraySlice(int[] array)
{
Dictionary<int, int> items = new Dictionary<int, int>();
int result = 0;
int startIndex = 0;
int uniqueItemCount = 0;
while (startIndex < array.Length)
{
items.Add(array[startIndex], startIndex);
uniqueItemCount = uniqueItemCount + 1;
for (int j = startIndex + 1; j < array.Length; j++)
{
if (items.ContainsKey(array[j]) == false)
{
if (uniqueItemCount != 2)
{
items.Add(array[j], j);
uniqueItemCount = uniqueItemCount + 1;
if (j == array.Length - 1)
{
result = Math.Max(result, j - startIndex + 1);
startIndex = array.Length;
break;
}
}
else if (uniqueItemCount == 2)
{
result = Math.Max(result, j - startIndex);
int item = array[j - 1];
int firstFoundIndex = 0;
for (int k = j - 1; k >= 0; k--)
{
if (array[k] != item)
{
firstFoundIndex = k + 1;
break;
}
}
startIndex = firstFoundIndex;
items.Clear();
uniqueItemCount = 0;
break;
}
}
else if (items.ContainsKey(array[j]) != false)
{
if (j == array.Length - 1)
{
result = Math.Max(result, j - startIndex + 1);
startIndex = array.Length;
break;
}
}
}
}
return result;
}
static void Main(string[] args)
{
string line = Console.ReadLine();
if (!line.Equals(""))
{
if (line.Length == 1)
{
Console.WriteLine("1");
}
else
{
try
{
line = Regex.Replace(line, @"\s+", "");
String[] items = line.Split(',');
int N = items.Length;
int[] input = new int[N];
for (int i = 0; i < N; i++)
input[i] = Int32.Parse(items[i]);
if (input.Length == 1)
{
Console.WriteLine("1");
}
else
{
int result1 = maxCommonArraySlice(input);
Console.WriteLine(result1);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
}
}
}
}
When you create a new Program.cs file and put the above code inside it with a Main() method, application waits you to enter some input from the console.
package com.arrayutilities;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;
public class MaxCommonArraySlice {
public static int maxCommonArraySlice(int[] array) {
Map<Integer, Integer> items = new HashMap<Integer, Integer>();
int result = 0;
int startIndex = 0;
int uniqueItemCount = 0;
while (startIndex < array.length) {
items.put(array[startIndex], startIndex);
uniqueItemCount = uniqueItemCount + 1;
for (int j = startIndex + 1; j < array.length; j++) {
if (items.get(array[j]) == null) {
if (uniqueItemCount != 2) {
items.put(array[j], j);
uniqueItemCount = uniqueItemCount + 1;
if (j == array.length - 1) {
result = Math.max(result, j - startIndex + 1);
startIndex = array.length;
break;
}
} else if (uniqueItemCount == 2) {
result = Math.max(result, j - startIndex);
int item = array[j-1];
int firstFoundIndex = 0;
for( int k=j-1; k>=0; k-- )
{
if( array[k] != item )
{
firstFoundIndex = k+1;
break;
}
}
startIndex = firstFoundIndex;
items.clear();
uniqueItemCount = 0;
break;
}
} else if (items.get(array[j]) != null) {
if (j == array.length - 1) {
result = Math.max(result, j - startIndex + 1);
startIndex = array.length;
break;
}
}
}
}
return result;
}
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
String line = in.nextLine();
if (!line.equals("")) {
if (line.length() == 1) {
System.out.println("1");
} else {
try {
line = line.replaceAll("\\s+", "");
String[] items = line.split(",");
int N = items.length;
int[] input = new int[N];
for (int i = 0; i < N; i++)
input[i] = Integer.valueOf(items[i]);
if (input.length == 1) {
System.out.println("1");
} else {
int result1 = maxCommonArraySlice(input);
System.out.println(result1);
}
} catch (Exception ex) {
System.out.println(ex.toString());
}
}
}
in.close();
}
}
When you create a new MaxCommonArraySlice.java file and put the above code inside it with a main() method, application waits you to enter some input from the console.
package datastructures.linkedlists;
class Node
{
int data;
Node next;
}
public class SinglyLinkedList {
Node head;
public SinglyLinkedList() {
head = null;
}
}
package datastructures.linkedlists;
public class SinglyLinkedListUtility {
public int CompareLists(Node headA, Node headB) {
if( headA == null || headB == null ) return 0;
Node walkA = headA;
Node walkB = headB;
while( walkA != null )
{
if( walkA.data != walkB.data ) return 0;
walkA = walkA.next;
walkB = walkB.next;
if( walkA==null && walkB!=null ) return 0;
if( walkA!=null && walkB==null ) return 0;
}
return 1;
}
}
TestSinglyLinkedListUtility is the unit test class including testCompareLists unit test method.package datastructures.linkedlists;
import static org.junit.Assert.*;
import org.junit.Test;
public class TestSinglyLinkedListUtility {
@Test
public void testCompareLists() {
Node node4 = new Node();
node4.data = 4;
Node node3 = new Node();
node3.data = 3;
node3.next = node4;
Node node2 = new Node();
node2.data = 2;
node2.next = node3;
Node node1 = new Node();
node1.data = 1;
node1.next = node2;
Node headA = node1;
Node node31 = new Node();
node31.data = 3;
node31.next = null;
Node node21 = new Node();
node21.data = 2;
node21.next = node31;
Node node11 = new Node();
node11.data = 1;
node11.next = node21;
Node headB = node11;
SinglyLinkedListUtility linkedListUtility = new SinglyLinkedListUtility();
assertEquals( linkedListUtility.CompareLists(headA, headB), 0 );
}
}
JUnit execution result is :
#include <iostream>
using namespace std;
void constPtrToData()
{
//not allowed to change where the ptr points to
int val1 = 10, val2 = 20;
int *const ptr = &val1;
cout << "\n";
cout << "ptr value = " << *ptr << " address = "<< ptr << "\n";
*ptr = val2;
cout << "\n";
cout << "ptr value = " << *ptr << " address = "<< ptr << "\n";
cout << "\n";
cout << "val1 value = " << val1 << " val2 value = " << val2 << "\n";
// can not assign to constant ptr a new address
// ptr = &val2; // error: assignment of read-only variable 'ptr'
}
int main()
{
constPtrToData();
cout << "\n";
return 0;
}
error: assignment of read-only location '* ptr2'
#include <iostream>
using namespace std;
void ptrToConstantData()
{
//protect the value of the variable pointed to
double val3 = 32, val4 = 45;
const double *ptr2 = &val3;
cout << "\n";
cout << "ptr2 value = " << *ptr2 << " address = " << ptr2 << "\n";
// can not change the value at the address ptr2 points to
// *ptr2 = val4; error: assignment of read-only location '* ptr2'
// allowed to change the address of the ptr2 points to
ptr2 = &val4;
cout << "\n";
cout << "ptr2 value = " << *ptr2 << " address = " << ptr2 << "\n";
cout << "\n";
cout << "val3 value = " << val3 << " val4 value = " << val4 << "\n";
}
int main()
{
ptrToConstantData();
cout << "\n";
return 0;
}
#include <iostream>
using namespace std;
void constPtrToConstData()
{
//protect both pointer and the data from being modified
int val1 = 10, val2 = 20;
const int *const ptr3 = &val1;
cout << *ptr3 << "\n";
// ptr3 = &val2; // error: assignment of read-only variable 'ptr3'
// *ptr3 = val2; // error: assignment of read-only location '*(const int*)ptr3'
}
int main()
{
constPtrToConstData();
cout << "\n";
return 0;
}
When the "constPtrToConstData()" function executed it just prints "10" as expected to the terminal.
