how to traverse a palindrome java using substring method code example
Example 1: Java program to check palindrome string using recursion
import java.util.Scanner;
public class RecursivePalindromeJava
{
public static boolean checkPalindrome(String str)
{
if(str.length() == 0 || str.length() == 1)
return true;
if(str.charAt(0) == str.charAt(str.length() - 1))
return checkPalindrome(str.substring(1, str.length() - 1));
return false;
}
public static void main(String[]args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Please enter a string : ");
String strInput = sc.nextLine();
if(checkPalindrome(strInput))
{
System.out.println(strInput + " is palindrome");
}
else
{
System.out.println(strInput + " not a palindrome");
}
sc.close();
}
}
Example 2: String palindrome in java using array
import java.util.Arrays;
import java.util.Scanner;
public class StringPalindromeUsingArray
{
public static void main(String[] args)
{
System.out.println("Please enter string to check whether string is palindrome: ");
Scanner sc = new Scanner(System.in);
String strInput = sc.nextLine();
char[] chArray = strInput.toCharArray();
int size = chArray.length;
char[] chGiven = Arrays.copyOf(chArray, chArray.length);
for(int a = 0; a < size / 2; a++)
{
char temp = chArray[a];
chArray[a] = chArray[size - a - 1];
chArray[size - a - 1] = temp;
}
System.out.println("Given array: " + Arrays.toString(chGiven));
System.out.println("String palindrome using array: " + Arrays.toString(chArray));
if(Arrays.equals(chArray, chGiven))
{
System.out.println("string is palindrome.");
}
else
{
System.out.println("string is not a palindrome.");
}
sc.close();
}
}