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 JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

const main = input =>{

    const arr = input.split(" ").map(n => Number(n));
    const num = arr[0];
    const need = arr[1];

    var output = 0;
    var result = 0;

    for(var i = 0; i < 20; i++ ){
        result ++;
        output += num;
        if(output >= need){
            break;
        }

        output --;
    }

    console.log(result);
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));