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 Perl (v5.18.2) (judge verdict: Wrong Answer)

#!/usr/bin/perl

sub main() {
  my($A,$B)=split(/ /,<>);
  chomp($B);
  my $ans = prob($A,$B);
  print $ans;
}

sub prob() {
  my($A,$B) = @_;
  if($B-$A <= 0){ return 1}
  for my $i(2..40){
    if($A*$i-($i-1) >= $B){
      return $i;
    }
  }
}

&main();