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.Linq;
using System.Text;
using System.Threading.Tasks;
class Program
{
  void Solve()
  {
    var N = ToInts();
    if (N[1]==1)
    {
      Console.WriteLine(0);
      return;
    }
    var ret = 1;
    var max = N[0];
    for(; ;)
    {
      if (max>=N[1])
        break;

      max += (N[0] - 1);

      ret += 1;
    }
    
    Console.WriteLine(ret); ;
  }
  static int[] ToInts()
  {
    var ss = Console.ReadLine().Split();
    var ret = new /**/int[ss.Length];
    for (int i=0;i<ss.Length ;i++)
    {
      ret[i] = /**/int.Parse(ss[i]);
    }
    return ret;
  }

  static void Main(string[] args)
  {
    new Program().Solve();
  }
}