CF1252K Addition Robot

Adding two numbers several times is a time-consuming task, so you want to build a robot. The robot should have a string $ S = S_1 S_2 \dots S_N $ of $ N $ characters on its memory that represents addition instructions. Each character of the string, $ S_i $ , is either 'A' or 'B'. You want to be able to give $ Q $ commands to the robot, each command is either of the following types: - 1 $ L $ $ R $ . The robot should toggle all the characters of $ S_i $ where $ L \le i \le R $ . Toggling a character means changing it to 'A' if it was previously 'B', or changing it to 'B' if it was previously 'A'. - 2 $ L $ $ R $ $ A $ $ B $ . The robot should call $ f(L, R, A, B) $ and return two integers as defined in the following pseudocode: ```

```
      function f(L, R, A, B):

      FOR i from L to R

        if S[i] = 'A'

          A = A + B

        else

          B = A + B

      return (A, B)


  ```
  ```

You want to implement the robot's expected behavior.
                            

N/A

N/A

Explanation for the sample input/output #1 For the first command, calling $ f(L, R, A, B) $ causes the following: - Initially, $ A = 1 $ and $ B = 1 $ . - At the end of $ i = 1 $ , $ A = 2 $ and $ B = 1 $ . - At the end of $ i = 2 $ , $ A = 2 $ and $ B = 3 $ . - At the end of $ i = 3 $ , $ A = 5 $ and $ B = 3 $ . - At the end of $ i = 4 $ , $ A = 8 $ and $ B = 3 $ . - At the end of $ i = 5 $ , $ A = 11 $ and $ B = 3 $ . Therefore, $ f(L, R, A, B) $ will return $ (11, 3) $ .For the second command, string $ S $ will be updated to "ABBBB". For the third command, the value of $ A $ will always be $ 0 $ and the value of $ B $ will always be $ 1\,000\,000\,000 $ . Therefore, $ f(L, R, A, B) $ will return $ (0, 1\,000\,000\,000) $ .