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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int	main(void)
{
  	int	a;
  	int	b;
 	int	num;
  	int	i;
  	int	n;
  
  	num = scanf("%d %d", &a, &b);
  	if (num != 2)
      	return (0);
  
  	for(i=0; i<11; i++)
    {
      	n = a * i + (i - 1);
      	if (n >= b)
        {
          	printf("%d", i);
			return (0);
        }
    }
  	return (0);
}