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.*;
import java.util.*;
import java.lang.*;

class Output extends PrintWriter {

    public Output(PrintStream io) {
        super(io);
    }

    public void printArray(int[] array, String space, String end) {
        int N = array.length;
        for(int n=0; n<N-1; n++){
            super.print(array[n]);
            super.print(space);
        }
        super.print(array[N-1]);
        super.print(end);
        super.flush();
    }
    public void printArray(int[] array){
        this.printArray(array, " ", "\n");
    }
    public void printArray(long[] array, String space, String end) {
        int N = array.length;
        for(int n=0; n<N-1; n++){
            super.print(array[n]);
            super.print(space);
        }
        super.print(array[N-1]);
        super.print(end);
        super.flush();
    }
    public void printArray(long[] array){
        this.printArray(array, " ", "\n");
    }
    public void printArray(double[] array, String space, String end) {
        int N = array.length;
        for(int n=0; n<N-1; n++){
            super.print(array[n]);
            super.print(space);
        }
        super.print(array[N-1]);
        super.print(end);
        super.flush();
    }
    public void printArray(double[] array){
        this.printArray(array, " ", "\n");
    }
    public void printArray(char[] array, String space, String end) {
        int N = array.length;
        for(int n=0; n<N-1; n++){
            super.print(array[n]);
            super.print(space);
        }
        super.print(array[N-1]);
        super.print(end);
        super.flush();
    }
    public void printArray(char[] array){
        this.printArray(array, " ", "\n");
    }
    public void printArray(Object[] array, String space, String end) {
        int N = array.length;
        for(int n=0; n<N-1; n++){
            super.print(array[n]);
            super.print(space);
        }
        super.print(array[N-1]);
        super.print(end);
        super.flush();
    }
    public void printArray(Object[] array){
        this.printArray(array, " ", "\n");
    }

}

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Output out = new Output(System.out);

        int A = sc.nextInt();
        int B = sc.nextInt();

        //solve 1 + (A-1)*X >= B
        for(int x=0; x<100; x++){
            if(1 + (A-1)*x >= B) {
                out.println(x);
                break;
            }
        }

        out.flush();
    }
}