write a go solution for Description:
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_1S_2...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<=i<=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.

Input Format:
Input begins with a line containing two integers: N Q (1<=N,Q<=100,000) representing the number of characters in the robot's memory and the number of commands, respectively. The next line contains a string S containing N characters (each either 'A' or 'B') representing the initial string in the robot's memory. The next Q lines each contains a command of the following types.

- 1 L R (1<=L<=R<=N)
- 2 L R A B (1<=L<=R<=N; 0<=A,B<=10^9)

Output Format:
For each command of the second type in the same order as input, output in a line two integers (separated by a single space), the value of A and B returned by f(L,R,A,B), respectively. As this output can be large, you need to modulo the output by 1,000,000,007.

Note:
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.

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).. Output only the code with no comments, explanation, or additional text.