add test 606

src/main/java/com/fishercoder/solutions/_396.java

@@ -52,10 +52,27 @@ private int[] rotate(int[] a) {
         a[a.length-1] = first;
         return a;
     }
+    //**credit : https://discuss.leetcode.com/topic/58459/java-o-n-solution-with-explanation
+    public int maxRotateFunction_1(int[] A) {
+        int allSum = 0;
+        int len = A.length;
+        int F = 0;
+        for (int i = 0; i < len; i++) {
+            F += i * A[i];
+            allSum += A[i];
+        }
+        int max = F;
+        for (int i = len - 1; i >= 1; i--) {
+            F = F + allSum - len * A[i];
+            max = Math.max(F, max);
+        }
+        return max;
+    }
 
     public static void main(String...strings){
         int[] nums = new int[]{4, 3, 2, 6};
         _396 test = new _396();
         System.out.println(test.maxRotateFunction(nums));
+        System.out.println(test.maxRotateFunction_1(nums));
     }
 }

src/test/java/com/fishercoder/_606Test.java

@@ -38,4 +38,12 @@ public void test2(){
         System.out.println("Test2");
         assertEquals("1(2()(4))(3)", test.tree2str(t));
     }
+    @Test
+    public void test3(){
+        t= new TreeNode(1);
+        t.right = new TreeNode(2);
+        t.right.right = new TreeNode(3);
+        System.out.println("Test3");
+        assertEquals("1()(2()(3))", test.tree2str(t));
+    }
 }