String in java

1]write a program to remove duplicates from a string.
  import java.util.LinkedHashSet;
import java.util.Set;

public class RemoveDuplicates {
  public static String removeDuplicates(String input) {
    Set<Character> set = new LinkedHashSet<>();
    for (int i = 0; i < input.length(); i++) {
      set.add(input.charAt(i));
    }
    StringBuilder sb = new StringBuilder();
    for (Character character : set) {
      sb.append(character);
    }
    return sb.toString();
  }

  public static void main(String[] args) {
    String input = "geeksforgeeks";
    System.out.println("Input string: " + input);
    System.out.println("After removing duplicates: " + removeDuplicates(input));
  }
}
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2] write a program to print duplicates characters from the string.
import java.util.HashMap;
import java.util.Map;

public class PrintDuplicates {
  public static void printDuplicates(String input) {
    Map<Character, Integer> map = new HashMap<>();
    for (int i = 0; i < input.length(); i++) {
      char c = input.charAt(i);
      if (map.containsKey(c)) {
        map.put(c, map.get(c) + 1);
      } else {
        map.put(c, 1);
      }
    }
    System.out.println("Duplicate characters:");
    for (Map.Entry<Character, Integer> entry : map.entrySet()) {
      if (entry.getValue() > 1) {
        System.out.println(entry.getKey());
      }
    }
  }

  public static void main(String[] args) {
    String input = "geeksforgeeks";
    System.out.println("Input string: " + input);
    printDuplicates(input);
  }
}
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3] write a program to check if “2552” is palindrome or not.
public class PalindromeCheck {
  public static boolean isPalindrome(String input) {
    int length = input.length();
    for (int i = 0; i < length / 2; i++) {
      if (input.charAt(i) != input.charAt(length - i - 1)) {
        return false;
      }
    }
    return true;
  }

  public static void main(String[] args) {
    String input = "2552";
    if (isPalindrome(input)) {
      System.out.println("The string " + input + " is a palindrome.");
    } else {
      System.out.println("The string " + input + " is not a palindrome.");
    }
  }
}
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4] write a program to count the number of consonants, vowels,special characters in string.
public class CharacterCounter {
  public static void countCharacters(String input) {
    int vowels = 0;
    int consonants = 0;
    int special = 0;
    for (int i = 0; i < input.length(); i++) {
      char c = input.charAt(i);
      if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U') {
        vowels++;
      } else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
        consonants++;
      } else {
        special++;
      }
    }
    System.out.println("Vowels: " + vowels);
    System.out.println("Consonants: " + consonants);
    System.out.println("Special characters: " + special);
  }

  public static void main(String[] args) {
    String input = "Hello, World!";
    System.out.println("Input string: " + input);
    countCharacters(input);
  }
}
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5]write a program to implement Anagram checking least in build method being used.
public class AnagramCheck {
  public static boolean isAnagram(String input1, String input2) {
    int length1 = input1.length();
    int length2 = input2.length();
    if (length1 != length2) {
      return false;
    }
    int[] frequency = new int[26];
    for (int i = 0; i < length1; i++) {
      frequency[input1.charAt(i) - 'a']++;
      frequency[input2.charAt(i) - 'a']--;
    }
    for (int count : frequency) {
      if (count != 0) {
        return false;
      }
    }
    return true;
  }

  public static void main(String[] args) {
    String input1 = "listen";
    String input2 = "silent";
    if (isAnagram(input1, input2)) {
      System.out.println("The strings " + input1 + " and " + input2 + " are anagrams.");
    } else {
      System.out.println("The strings " + input1 + " and " + input2 + " are not anagrams.");
    }
  }
}