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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;
 
int main() {
  int A,B;
  // 変数aで入力を受け取る
  cin >> A;
  cin >> B;
  int sum = 1;
  int count =0;

  //cout << B;

  for(int i =0;true;i++){
      sum = sum + A-1;
      //cout << i;
      if(sum >= B){
          //cout << sum;
          count = i;
          break;
      }
  }
  if(B == 1){
      cout << 0 << endl;
  }else{
      cout << count+1 << endl;
  }
}