refactor 89

fishercoder1534 · fishercoder1534 · commit 30bdd4cac719 · 2018-03-02T08:08:10.000-08:00
diff --git a/src/main/java/com/fishercoder/solutions/_89.java b/src/main/java/com/fishercoder/solutions/_89.java
@@ -1,7 +1,5 @@
 package com.fishercoder.solutions;
 
-import com.fishercoder.common.utils.CommonUtils;
-
 import java.util.ArrayList;
 import java.util.List;
 
@@ -31,19 +29,14 @@
 
 public class _89 {
 
+  public static class Solution1 {
     public List<Integer> grayCode(int n) {
-        List<Integer> result = new ArrayList();
-        for (int i = 0; i < (1 << n); i++) {
-            result.add(i ^ (i >> 1));
-        }
-        return result;
+      List<Integer> result = new ArrayList();
+      for (int i = 0; i < (1 << n); i++) {
+        result.add(i ^ (i >> 1));
+      }
+      return result;
     }
+  }
 
-    public static void main(String... args) {
-        int n = 3;
-        System.out.println("1 << n = " + (1 << n));
-        _89 test = new _89();
-        List<Integer> result = test.grayCode(n);
-        CommonUtils.printList(result);
-    }
 }
diff --git a/src/test/java/com/fishercoder/_89Test.java b/src/test/java/com/fishercoder/_89Test.java
@@ -0,0 +1,23 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._89;
+import java.util.Arrays;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _89Test {
+
+  private static _89.Solution1 solution1;
+
+  @BeforeClass
+  public static void setup() {
+    solution1 = new _89.Solution1();
+  }
+
+  @Test
+  public void test1() {
+    assertEquals(Arrays.asList(0, 1, 3, 2, 6, 7, 5, 4), solution1.grayCode(3));
+  }
+}
