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)

// Created by sz
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
#ifdef LOCAL
    freopen("./input.txt", "r", stdin);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    
    int a,b;
    cin >> a >> b;
    
    int cnt = 0;
    int sum = 1;
    while (sum < b) {
        cnt ++;
        sum += a-1;
    }
    
    cout << cnt << "\n";
    
    return 0;
}