Display String Palindrome In Java Using For Loop

Display string palindrome in java using for loop

A string is said to be a palindrome if it is the same if we start reading it from left to right or right to left. So let us consider a string “str”, now the task is just to find out with its reverse string is the same as it is.

Input : str = “radar”

Output: Yes

Example 1:

To find the a Palindrome in Java. There is simple method, we will first reverse the string or number and compare the reversed string or number with the original value.

Method 1: Java Program to Check Palindrome String

class Main {
public static void main(String[] args) {

String str = "Radar", reverseStr = "";

int strLength = str.length();

for (int i = (strLength - 1); i >=0; --i) {
  reverseStr = reverseStr + str.charAt(i);
}

if (str.toLowerCase().equals(reverseStr.toLowerCase())) {
  System.out.println(str + " is a Palindrome String.");
}
else {
  System.out.println(str + " is not a Palindrome String.");
}

}
}

Output:

Radar is a Palindrome String.

Example 2:

This Java program asks the user to provide a string input and checks it for the Palindrome String.

Scanner class and its function nextLine() is used to obtain the input, and println() function is used to print on the screen.
Scanner class is a part of java.util package, so we required to import this package in our Java program.
We also required to create an object of Scanner class to call its functions.

Method 2: Program to display given user input is Palindrome or not

import java.util.Scanner;
 
class ChkPalindrome
{
   public static void main(String args[])
   {
      String str, rev = "";
      Scanner sc = new Scanner(System.in);
 
      System.out.println("Enter a string:");
      str = sc.nextLine();
 
      int length = str.length();
 
      for ( int i = length - 1; i >= 0; i-- )
         rev = rev + str.charAt(i);
 
      if (str.equals(rev))
         System.out.println(str+" is a palindrome");
      else
         System.out.println(str+" is not a palindrome");
 
   }
}

Output:

Enter a string:

radar

radar is a palindrome

Example 3:

In the below example, we have a number 3553 stored in num and originalNum variables. Here, we have used the

while loop to reverse num and store the reversed number in reversedNum
if…else to check if reversedNum is same as the originalNum

Method 3: Java Program to Check Palindrome Number

class Main {
public static void main(String[] args) {

int num = 3553, reversedNum = 0, remainder;

// store the number to originalNum
int originalNum = num;

// get the reverse of originalNum
// store it in variable
while (num != 0) {
  remainder = num % 10;
  reversedNum = reversedNum * 10 + remainder;
  num /= 10;
}

// check if reversedNum and originalNum are equal
if (originalNum == reversedNum) {
  System.out.println(originalNum + " is Palindrome.");
}
else {
  System.out.println(originalNum + " is not Palindrome.");
}

}
}

Output:

3553 is Palindrome.

Display string palindrome in java using for loop – Display string palindrome in java using for loop – Display string palindrome in java using for loop – Display string palindrome in java using for loop

TEST

Display string palindrome in java using for loop