feat:Add SwapNumbersUsingXor algo with JUnit tests

Author: Tanmay-Singh3004

DIRECTORY.md

@@ -45,6 +45,7 @@
             * [SingleBitOperations](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SingleBitOperations.java)
             * [SingleElement](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SingleElement.java)
             * [SwapAdjacentBits](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SwapAdjacentBits.java)
+            * [SwapNumbersUsingXor](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SwapNumbersUsingXor.java)
             * [TwosComplement](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/TwosComplement.java)
           * ciphers
             * a5
@@ -676,6 +677,7 @@
             * [SingleBitOperationsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SingleBitOperationsTest.java)
             * [SingleElementTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SingleElementTest.java)
             * [SwapAdjacentBitsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SwapAdjacentBitsTest.java)
+            * [SwapNumbersUsingXorTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SwapNumbersUsingXorTest.java)
             * [TwosComplementTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/TwosComplementTest.java)
           * ciphers
             * a5

src/main/java/com/thealgorithms/bitmanipulation/SwapNumbersUsingXor.java

@@ -0,0 +1,53 @@
+package com.thealgorithms.bitmanipulation;
+
+/**
+ * <pre>
+ * This class provides a method to swap two numbers using XOR without creating a third variable.
+ *
+ * The XOR swap algorithm works as follows:
+ *
+ * Let's say we have two numbers, a and b.
+ *
+ * Step 1: a = a ^ b
+ * - This step stores the XOR of a and b in a.
+ * - Example: If a = 5 (0101 in binary) and b = 3 (0011 in binary),
+ *   then a = 5 ^ 3 = 6 (0110 in binary).
+ *
+ * Step 2: b = a ^ b
+ * - This step updates b to the original value of a.
+ * - Example: Now a = 6 (0110 in binary) and b = 3 (0011 in binary),
+ *   then b = 6 ^ 3 = 5 (0101 in binary).
+ *
+ * Step 3: a = a ^ b
+ * - This step updates a to the original value of b.
+ * - Example: Now a = 6 (0110 in binary) and b = 5 (0101 in binary),
+ *   then a = 6 ^ 5 = 3 (0011 in binary).
+ *
+ * After these three steps, the values of a and b are swapped.
+ *
+ * For more information, refer to the
+ * <a href="https://en.wikipedia.org/wiki/XOR_swap_algorithm"> XOR swap algorithm </a>.
+ *
+ * Example usage:
+ * <code>
+ * int[] result = SwapNumbersUsingXor.swap(5, 3);<br>
+ * System.out.println("After swap: a = " + result[0] + ", b = " + result[1]);
+ * </code>
+ * </pre>
+ */
+public class SwapNumbersUsingXor {
+
+    /**
+     * Swaps two numbers using XOR.
+     *
+     * @param a the first number
+     * @param b the second number
+     * @return an array containing the swapped numbers
+     */
+    public static int[] swap(int a, int b) {
+        a = a ^ b; // Step 1
+        b = a ^ b; // Step 2
+        a = a ^ b; // Step 3
+        return new int[] {a, b};
+    }
+}

src/test/java/com/thealgorithms/bitmanipulation/SwapNumbersUsingXorTest.java

@@ -0,0 +1,47 @@
+package com.thealgorithms.bitmanipulation;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Unit tests for the SwapNumbersUsingXor class.
+ */
+public class SwapNumbersUsingXorTest {
+
+    /**
+     * Test the swap method with positive numbers.
+     */
+    @Test
+    public void testSwapPositiveNumbers() {
+        int[] result = SwapNumbersUsingXor.swap(5, 3);
+        assertArrayEquals(new int[] {3, 5}, result);
+    }
+
+    /**
+     * Test the swap method with negative numbers.
+     */
+    @Test
+    public void testSwapNegativeNumbers() {
+        int[] result = SwapNumbersUsingXor.swap(-5, -3);
+        assertArrayEquals(new int[] {-3, -5}, result);
+    }
+
+    /**
+     * Test the swap method with a positive and a negative number.
+     */
+    @Test
+    public void testSwapPositiveAndNegativeNumbers() {
+        int[] result = SwapNumbersUsingXor.swap(5, -3);
+        assertArrayEquals(new int[] {-3, 5}, result);
+    }
+
+    /**
+     * Test the swap method with zero.
+     */
+    @Test
+    public void testSwapWithZero() {
+        int[] result = SwapNumbersUsingXor.swap(0, 3);
+        assertArrayEquals(new int[] {3, 0}, result);
+    }
+}