Added Shuffle Algorithm

Fisher-Yates (Knuth) Shuffle algorithm randomly permutes an array's elements, ensuring each permutation is equally likely.
TheAlgorithms · siriak · Oct 29, 2024 · Oct 26, 2024 · Oct 26, 2024 · Oct 26, 2024
commit 53b36994752c409feb590d4fbebc8fbce321c267
@@ -0,0 +1,73 @@
+package com.thealgorithms.misc;
+import java.util.Random;
+import java.util.Scanner;
+/**
+ * The Fisher-Yates (Knuth) Shuffle algorithm randomly permutes an array's
+ * elements, ensuring each permutation is equally likely.
+ *
+ * <p>
+ * Worst-case performance O(n)
+ * Best-case performance O(n)
+ * Average performance O(n)
+ * Worst-case space complexity O(1)
+ *
+ * This class provides a static method to shuffle an array in place.
+ *
+ * @author Your Name (https://github.com/Chiefpatwal)
+ */
+public final class ShuffleArray {
+    // Prevent instantiation
+    private ShuffleArray() {
+    }
+    /**
+     * This method shuffles an array using the Fisher-Yates algorithm.
+     *
+     * @param arr is the input array to be shuffled
+     */
+    public static void shuffle(int[] arr) {
+        Random random = new Random();
+        for (int i = arr.length - 1; i > 0; i--) {
+            int j = random.nextInt(i + 1);
+            int temp = arr[i];
+            arr[i] = arr[j];
+            arr[j] = temp;
+        }
+    }
+    /**
+     * This method takes user input to create an array.
+     *
+     * @return the array created from user input
+     */
+    public static int[] getUserInputArray() {
+        Scanner scanner = new Scanner(System.in);
+        System.out.print("Enter the size of the array: ");
+        int size = scanner.nextInt();
+
+        int[] arr = new int[size];
+        System.out.println("Enter " + size + " elements:");
+        for (int i = 0; i < size; i++) {
+            arr[i] = scanner.nextInt();
+        }
+        return arr;
+    }
+    public static void main(String[] args) {
+        int[] userArray = getUserInputArray();
+        System.out.println("Original Array:");
+        printArray(userArray);
+
+        shuffle(userArray);
+        System.out.println("Shuffled Array:");
+        printArray(userArray);
+    }
+    /**
+     * This method prints the elements of the array.
+     *
+     * @param arr is the input array to be printed
+     */
+    public static void printArray(int[] arr) {
+        for (int num : arr) {
+            System.out.print(num + " ");
+        }
+        System.out.println();
+    }
+}