add a solution for 461

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_461.java

@@ -12,4 +12,22 @@ public int hammingDistance(int x, int y) {
             return count;
         }
     }
+
+    public static class Solution2 {
+        public int hammingDistance(int x, int y) {
+            int ans = 0;
+            for (int i = 0; i < 32; i++) {
+                ans += (x & 1) ^ (y & 1);
+                x >>= 1;
+                y >>= 1;
+            }
+            return ans;
+        }
+    }
+
+    public static class Solution3 {
+        public int hammingDistance(int x, int y) {
+            return Integer.bitCount(x ^ y);
+        }
+    }
 }

src/test/java/com/fishercoder/_461Test.java

@@ -0,0 +1,44 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._461;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _461Test {
+    private static _461.Solution1 solution1;
+    private static _461.Solution2 solution2;
+    private static _461.Solution3 solution3;
+    private static int x;
+    private static int y;
+    private static int expected;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _461.Solution1();
+        solution2 = new _461.Solution2();
+        solution3 = new _461.Solution3();
+    }
+
+    @Test
+    public void test1() {
+        x = 1;
+        y = 4;
+        expected = 2;
+        assertEquals(expected, solution1.hammingDistance(x, y));
+        assertEquals(expected, solution2.hammingDistance(x, y));
+        assertEquals(expected, solution3.hammingDistance(x, y));
+    }
+
+    @Test
+    public void test2() {
+        x = 3;
+        y = 1;
+        expected = 1;
+        assertEquals(expected, solution1.hammingDistance(x, y));
+        assertEquals(expected, solution2.hammingDistance(x, y));
+        assertEquals(expected, solution3.hammingDistance(x, y));
+    }
+
+}