Problem:
Score : 200 points

Problem Statement

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 1

4 10

Sample Output 1

3

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

Sample Input 2

8 9

Sample Output 2

2

2 power strips, each with 8 sockets, extend the socket into 15 empty sockets.

Sample Input 3

8 8

Sample Output 3

1

Solution in C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;

class Program
{
	static int Main(string[] args)
	{
		string[] con = Console.ReadLine().Split(' ');
		int A = int.Parse(con[0]);
		int B = int.Parse(con[1]);
		int tap = A;
		int kosu = 1;
		
		if(B==1) {
			Console.WriteLine("0");
			return 0;
		}
		
		while (B >= tap) {
			kosu++;
			tap = tap + A - 1;
		}
		Console.WriteLine(kosu);
		return 0;
	}
}