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: Wrong Answer)

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

namespace AtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            //[summary]B - Power Socket
            var line = ReadLine();
            int A = line[0];
            int B = line[1];

            int ans = (B - A) / (A - 1) + 1;

            if ((B - A) % (A - 1) != 0)
            {
                ans++;
            }

            Console.WriteLine(ans);
        }

        static List<int> ReadLine()
        {
            var line = Console.ReadLine();
            var arr = line.Split(' ');

            return arr.Select(x => int.Parse(x)).ToList();
        }
    }
}