Takahashi's house has only one socket.
Takahashi wants to extend it with some number of power strips, each with A sockets, into B or more empty sockets.
One power strip with A sockets can extend one empty socket into A empty sockets.
Find the minimum number of power strips required.

-----Constraints-----
- All values in input are integers.
- $2 \leq A \leq 20$
- $1 \leq B \leq 20$

-----Input-----
Input is given from Standard Input in the following format:
A B

-----Output-----
Print the minimum number of power strips required.

-----Sample Input-----
4 10

-----Sample Output-----
3

3 power strips, each with 4 sockets, extend the socket into 10 empty sockets.

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