Update Solution.java

Author: ThanhNIT

src/main/java/g3101_3200/s3101_count_alternating_subarrays/Solution.java

@@ -18,7 +18,7 @@ public long countAlternatingSubarrays(int[] nums) {
                 end++;
             }
         }
-        length = end -(long) start;
+        length = end - (long) start;
         count += (length * (length + 1)) / 2;
         return count;
     }