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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.IOException;
import java.io.InputStreamReader;
import java.io.BufferedReader;

public class Main {
	public static void main(String srgs[]) {
		BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
		try {
			String[] s = reader.readLine().split(" ");
			int A = Integer.parseInt(s[0]);
			int B = Integer.parseInt(s[1]);

			int c = (B - 1) / (A - 1);
			if ((B - 1) % (A - 1) != 0) {
				c += 1;
			}

			System.out.println(c);

		} catch (IOException e) {
			e.printStackTrace();
		}
	}

}