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 Kotlin (1.3.71) (judge verdict: Wrong Answer)

import java.util.Scanner;

fun main (args : Array<String>) {
  val input = Scanner(System.`in`);
  
  while (input.hasNext()) {
    val A = input.nextInt()
    val B = input.nextInt()
    var num = (B - 1) / (A - 1) + if ((B - 1) % (A - 1) != 0) 1 else 0
    
    if (num == 0) {
      ++num
    }
    
    println(num)
  }
}