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 Java7 (OpenJDK 1.7.0) (judge verdict: Accepted)

import java.util.*;

class Main {
	public static void main(String[] arg) {
		Scanner sc = new Scanner(System.in);
		int A = Integer.parseInt(sc.next());
		int B = Integer.parseInt(sc.next());
		int s= 0;
		
		if(B == 1) {
			System.out.println(0);
			return;
		}
		
		for(int i = 1;;i++){
			if((i*(A-1)) + 1 >= B){
				s = i;
				break;
			}
			
		}
		System.out.println(s);
	}
}