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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Collections;
using System.Linq;
using System.IO;

class Program
{
    static void Main(string[] args)
    {
        var tmp = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToArray();

        var A = tmp[0];
        var B = tmp[1];

        int n;

        var flag = ((B - 1) % (A - 1)) == 0;

        if (flag)
        {
            n = (B - 1) / (A - 1);
        }
        else
        {
            n = (B - 1) / (A - 1) + 1;
        }

        Console.WriteLine(n);
    }
}