CF1624F Interacdive Problem
Description
This problem is interactive.
We decided to play a game with you and guess the number $ x $ ( $ 1 \le x < n $ ), where you know the number $ n $ .
You can make queries like this:
- + c: this command assigns $ x = x + c $ ( $ 1 \le c < n $ ) and then returns you the value $ \lfloor\frac{x}{n}\rfloor $ ( $ x $ divide by $ n $ and round down).
You win if you guess the current number with no more than $ 10 $ queries.
Input Format
N/A
Output Format
The interaction begins by reading an integer $ n $ ( $ 2 < n \le 1000 $ ), which is written in the input data on its own line.
Then you can make no more than $ 10 $ queries. To make a query, print on a separate line:
- + c: this command will assign $ x = x + c $ ( $ 1 \le c < n $ ) and then print $ \lfloor\frac{x}{n}\rfloor $ (divide $ x $ by $ n $ and round down) on a separate line.
Print the answer, like the queries, on a separate line. The answer doesn't count in number of queries. To output it, use the following format:
- ! x: the current value of $ x $ .
After that, your program should exit.
You have to use a flush operation right after printing each line. For example, in C++ you should use the function fflush(stdout), in Java — System.out.flush(), in Pascal — flush(output) and in Python — sys.stdout.flush().
Note that the interactor is not responsive.
To make a hack, use the following format: a single line must contain two numbers $ x $ and $ n $ , separated by a space.
Explanation/Hint
In the first sample initially $ x = 2 $ . After the first query $ x = 3 $ , $ \lfloor\frac{x}{n}\rfloor = 1 $ .
In the second sample also initially $ x = 2 $ . After the first query $ x = 3 $ , $ \lfloor\frac{x}{n}\rfloor = 0 $ . After the second query $ x = 4 $ , $ \lfloor\frac{x}{n}\rfloor = 0 $ . After the third query $ x=5 $ , $ \lfloor\frac{x}{n}\rfloor = 1 $ .