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 (1.0.0) (judge verdict: Accepted)

fun main(args: Array<String>) {

    val (a, b) = readLine()!!.split(" ").map(String::toInt)

    println(method139B(a, b))
}

fun method139B(a: Int, b: Int): Any? {

    val zouka = a - 1

//    return (b - 1 ) / zouka の斬り上げ計算
    return ((b - 1) + zouka - 1) / zouka

//    var unused = 1
//    var count = 0
//    while (true) {
//        if (unused > b) {
//            break
//        }
//
//        count++
//        unused += a - 1
//    }
//
//    return count
}