B"This is an interactive problem. There is an unknown integer x ( 1 <= x <= n ). You want to find x . At first, you have a set of integers {1, 2, ldots, n } . You can perform the following operations no more than 10000 times: Remember that in the operation of type B a>1 must hold. Write a program, that will find the value of x . The first line contains one integer n ( 1 <= n <= 10^5 ). The remaining parts of the input will be given throughout the interaction process. In each round, your program needs to print a line containing one uppercase letter A, B or C and an integer a ( 1 <= a <= n for operations A and C, 2 <= a <= n for operation B). This line desribes operation you make. If your operation has type C your program should terminate immediately. Else your program should read one line containing a single integer, which is the answer to your operation. After outputting each line, don't forget to flush the output. To do it use: It is guaranteed, that the number x is fixed and won't change during the interaction process. Hacks: To make a hack, use such input format: The only line should contain two integers n , x ( 1 <= q x <= q n <= q 10^5 ). Note that to make the sample more clear, we added extra empty lines. You shouldn't print any extra empty lines during the interaction process. In the first test n=10 and x=4 . Initially the set is: {1,2,3,4,5,6,7,8,9,10 } . In the first operation, you ask how many numbers are multiples of 4 and delete them. The answer is 2 because there are two numbers divisible by 4 : {4,8 } . 8 will be deleted but 4 won't, because the number x will never be deleted. Now the set is {1,2,3,4,5,6,7,9,10 } . In the second operation, you ask how many numbers are multiples of 2 . The answer is 4 because there are four numbers divisible by 2 : {2,4,6,10 } . In the third "...