refactor 89

fishercoder1534 · fishercoder1534 · commit 24dbdf14542d · 2020-05-09T07:18:34.000-07:00
diff --git a/src/main/java/com/fishercoder/solutions/_89.java b/src/main/java/com/fishercoder/solutions/_89.java
@@ -3,69 +3,45 @@
 import java.util.ArrayList;
 import java.util.List;
 
-/**
- * 89. Gray Code
- *
- * The gray code is a binary numeral system where two successive values differ in only one bit.
- * Given a non-negative integer n representing the total number of bits in the code,
- * print the sequence of gray code.
- * A gray code sequence must begin with 0.
-
- For example, given n = 2, return [0,1,3,2]. Its gray code sequence is:
-
- 00 - 0
- 01 - 1
- 11 - 3
- 10 - 2
-
- Note:
-
- For a given n, a gray code sequence is not uniquely defined.
-
- For example, [0,2,3,1] is also a valid gray code sequence according to the above definition.
-
- For now, the judge is able to judge based on one instance of gray code sequence. Sorry about that.
- */
-
 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;
+    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;
+        }
     }
-  }
 
-  public static class Solution2 {
-    public List<Integer> grayCode(int n) {
-      List<Integer> result = new ArrayList();
-      for (int i = 0; i < Math.pow(2, n); i++) {
-        result.add(i ^ (i >> 1));
-      }
-      return result;
+    public static class Solution2 {
+        public List<Integer> grayCode(int n) {
+            List<Integer> result = new ArrayList();
+            for (int i = 0; i < Math.pow(2, n); i++) {
+                result.add(i ^ (i >> 1));
+            }
+            return result;
+        }
     }
-  }
 
-  public static void main(String... args) {
-    System.out.println("-----------------------------------------------------------------------------------------");
-    System.out.println("How to understand i << n? It means n to the power of two, see below. So we have an equivalent solution, which is solution2.");
-    System.out.println("1 << 2: " + (1 << 2));
-    System.out.println("1 << 3: " + (1 << 3));
-    System.out.println("1 << 4: " + (1 << 4));
-    System.out.println("1 << 5: " + (1 << 5));
-    System.out.println("1 << 6: " + (1 << 6));
-    System.out.println("-----------------------------------------------------------------------------------------");
-    System.out.println("How to understand i >> 1? It means to shift the number i to the right by 1 bit, see below");
-    System.out.println("0 >> 1: " + (0 >> 1));
-    System.out.println("1 >> 1: " + (1 >> 1));
-    System.out.println("2 >> 1: " + (2 >> 1));
-    System.out.println("3 >> 1: " + (3 >> 1));
-    System.out.println("4 >> 1: " + (4 >> 1));
-    System.out.println("5 >> 1: " + (5 >> 1));
-    System.out.println("6 >> 1: " + (6 >> 1));
-  }
+    public static void main(String... args) {
+        System.out.println("-----------------------------------------------------------------------------------------");
+        System.out.println("How to understand i << n? It means n to the power of two, see below. So we have an equivalent solution, which is solution2.");
+        System.out.println("1 << 2: " + (1 << 2));
+        System.out.println("1 << 3: " + (1 << 3));
+        System.out.println("1 << 4: " + (1 << 4));
+        System.out.println("1 << 5: " + (1 << 5));
+        System.out.println("1 << 6: " + (1 << 6));
+        System.out.println("-----------------------------------------------------------------------------------------");
+        System.out.println("How to understand i >> 1? It means to shift the number i to the right by 1 bit, see below");
+        System.out.println("0 >> 1: " + (0 >> 1));
+        System.out.println("1 >> 1: " + (1 >> 1));
+        System.out.println("2 >> 1: " + (2 >> 1));
+        System.out.println("3 >> 1: " + (3 >> 1));
+        System.out.println("4 >> 1: " + (4 >> 1));
+        System.out.println("5 >> 1: " + (5 >> 1));
+        System.out.println("6 >> 1: " + (6 >> 1));
+    }
 
 }
