Palindrome Checker Program: Verify if a String is Palindrome
Check String Length in string is a common operation in Java programming. It helps in various scenarios, such as determining the Counting of a user input or validating the input length against certain criteria. In the following sections, we will explore different approaches to accomplish this task efficiently.
Initializing the String
Before we begin counting the characters, we need to have a string to work with. In Java, you can initialize a string using the String
class.
String str= "String is Palendrome";
Using the length()
Method
The simplest way to count the characters in a string is by using the length()
method provided by the String
class. This method returns the number of characters in the string.
str.length();
Using the Condition to check String is boolean
Another approach to count the characters in a string is by using a loop. We can iterate over each character in the string and increment a counter variable.
str = str.toLowerCase(); // Convert the string to lowercase for case-insensitive comparison int left = 0; int right = str.length() - 1; while (left < right) { if (str.charAt(left) != str.charAt(right)) { return false; } left++; right--; }
Performance Considerations
When counting characters in a string, it’s important to consider performance. The length()
method has a time complexity of O(1) as it directly returns the length. However, using a loop to count characters has a time complexity of O(n) since it iterates over each character.
Sample code
public class Stringispalendrome{ public static void main(String[] args) { String input = "madam"; // Example input string if (isPalindrome(input)) { System.out.println("The string is a palindrome."); } else { System.out.println("The string is not a palindrome."); } } public static boolean isPalindrome(String str) { str = str.toLowerCase(); // Convert the string to lowercase for case-insensitive comparison int left = 0; int right = str.length() - 1; while (left < right) { if (str.charAt(left) != str.charAt(right)) { return false; } left++; right--; } return true; } }
In this program, we have directly assigned a string to the input
variable for demonstration purposes. You can modify the value of input
to test different strings. The isPalindrome
function is the same as in the previous example, which checks whether the string is a palindrome or not. After calling the function, the program prints the appropriate message based on the result.
Remember to replace the input
variable with the string you want to check for palindrome property.