JavaAnagrams.java

// https://www.hackerrank.com/challenges/java-anagrams/problem

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class JavaAnagrams {
 public static void main(String[] args) {
 Scanner scanner = new Scanner(System.in);
 String a = scanner.nextLine();
 String b = scanner.nextLine();

 if (isAnagram(a, b)) {
 System.out.println("Anagrams");
 } else {
 System.out.println("Not Anagrams");
 }
 }

 private static boolean isAnagram(String a, String b) {
 int[] aCharacterFrequencies = getCharacterFrequencies(a);
 int[] bCharacterFrequencies = getCharacterFrequencies(b);
 return areEqual(aCharacterFrequencies, bCharacterFrequencies);
 }

 private static int[] getCharacterFrequencies(String string) {
 int[] result = new int[26];
 string = string.toLowerCase();
 for (int index = 0 ; index < string.length() ; index++) {
 result[string.charAt(index) - 97]++;
 }
 return result;
 }

 private static boolean areEqual(int[] a, int[] b) {
 for (int index = 0 ; index < a.length ; index++) {
 if (a[index] != b[index]) {
 return false;
 }
 }
 return true;
 }

 private static boolean areAnagrams(String a, String b) {
 Map<Character, Integer> aCharacterFrequencies = getFrequencies(a);
 Map<Character, Integer> bCharacterFrequencies = getFrequencies(b);
 return aCharacterFrequencies.equals(bCharacterFrequencies);
 }

 private static Map<Character, Integer> getFrequencies(String string) {
 Map<Character, Integer> frequencies = new HashMap<>();
 string = string.toLowerCase();
 for (int index = 0 ; index < string.length() ; index++) {
 char character = string.charAt(index);
 frequencies.put(character, frequencies.getOrDefault(character, 0) + 1);
 }
 return frequencies;
 }
}