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: Accepted)

// AtCoder165 C

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <math.h>
#include <assert.h>
#include <string.h>
#include <memory.h>
#include <malloc.h>
#include <stdlib.h>

// qsortで用いる比較用関数．*a<*bならaが先になる．
int compare(const void* a, const void* b) {
    return *(int*)a - *(int*)b;
}

int main() {
    int i,j;
    double a,b;
    int sum = 0;

    scanf("%lf %lf", &a, &b);

    printf("%d", (int)ceil( (b-1)/(a-1) ));

    return 0;
}