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.util.Scanner;

public class Main {
	public static void main(String[] args){
		int A,B;
		Scanner sc = new Scanner(System.in);
		A = sc.nextInt();
		B = sc.nextInt();
		Main main = new Main();
		main.Count(A, B);
	}

	private void Count(int A,int B) {
		if (B==1) {
			System.out.println(0);
			return;
		}
		if (B<=A) {
			System.out.println(1);
			return;
		}
		int now = A;
		for (int i=1;i<100;i++) {
			now +=A-1;
			if (now >=B) {
				System.out.println(i+1);
				return;
			}
		}
	}
}