Feature: Moore's voting algorithm is added to find majority element in List/Array

Author: dhavalkgit

src/main/java/com/thealgorithms/datastructures/hashmap/hashing/MajorityElement.java

@@ -1,16 +1,73 @@
 package com.thealgorithms.datastructures.hashmap.hashing;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Optional;
 /*
-This class finds the majority element(s) in an array of integers.
+This class finds the majority element(s) in an array/List of integers.
 A majority element is an element that appears more than or equal to n/2 times, where n is the length
 of the array.
 */
 public final class MajorityElement {
-    private MajorityElement() {
+    private MajorityElement(){}
+
+   /**
+     * This method uses Moore's voting algorithm to find the majority element in the list.
+     * If a majority element is present, it returns the element; otherwise, it returns Optional.empty().
+     * @param <T> The type of elements in the list
+     * @param elements List of any type
+     * @return Optional of majority element or empty if none found
+     */
+    public static <T> Optional<T> majorityElement(List<T> elements) {
+        if (elements == null || elements.isEmpty()) {
+            return Optional.empty();  // Handle empty list case
+        }
+
+        T currentElement = elements.get(0);
+        long frequency = 1;
+
+        // Moore's Voting Algorithm to find potential majority element
+        for (int i = 1; i < elements.size(); i++) {
+            if (frequency == 0) {
+                currentElement = elements.get(i);
+                frequency = 1;
+            } else if (!currentElement.equals(elements.get(i))) {
+                frequency--;
+            } else {
+                frequency++;
+            }
+        }
+
+        // Second pass to confirm if it occurs more than n/2 times
+        long count = 0;
+        for (T element : elements) {
+            if (element.equals(currentElement)) {
+                count++;
+            }
+        }
+
+        if (count > elements.size() / 2) {
+            return Optional.of(currentElement);
+        } else {
+            return Optional.empty();
+        }
+    }
+
+    /**
+     * Method to handle array input and convert to list.
+     * @param <T> The type of elements in the array
+     * @param elements Array of any type
+     * @return Optional of majority element or empty if none found
+     */
+    public static <T> Optional<T> majorityElement(T[] elements) {
+        if (elements == null || elements.length == 0) {
+            return Optional.empty();  // Handle empty array case
+        }
+        return majorityElement(Arrays.asList(elements));
     }
+    
     /*
    This method returns the majority element(s) in the given array of integers.
    @param nums: an array of integers