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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
 
public class Main {
	public static void main(String[] args) throws IOException, Exception{
		BufferedReader st = new BufferedReader(new InputStreamReader(System.in));
		int[] data = getIntArry(st);
		int m = data[0];
		int t = data[1];
		int cnt = 1;
		int t2 = m;
		while(t2 < t) {
			t2+=(m - 1);
			cnt++;
		}
		if (t == 1) {
			cnt = 0;
		}
		anser(cnt);
	}
 
	private static int[] getIntArry(BufferedReader st) throws Exception, IOException {
		String line = st.readLine();
		String[] strData = line.split(" ");
		int[] intData = new int[strData.length];
		for (int i = 0; i < strData.length; i++) {
			intData[i] = Integer.parseInt(strData[i]);
		}
		return intData;
	}
 
	private static void anser(int num) {
		System.out.println(num);
	}
}