refactor 136

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_136.java

@@ -6,10 +6,18 @@
 
 /**136. Single Number
 
-Given an array of integers, every element appears twice except for one. Find that single one.
+ Given a non-empty array of integers, every element appears twice except for one. Find that single one.
 
-Note:
-Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?
+ Note:
+ Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?
+
+ Example 1:
+ Input: [2,2,1]
+ Output: 1
+
+ Example 2:
+ Input: [4,1,2,1,2]
+ Output: 4
 */
 
 public class _136 {
@@ -28,8 +36,7 @@ public int singleNumber(int[] nums) {
           set.remove(i);
         }
       }
-      Iterator<Integer> it = set.iterator();
-      return it.next();
+      return set.iterator().next();
     }
   }