Sum of Integers

Time Limit : 1 sec, Memory Limit : 65536 KB
Japanese version is here

Sum of Integers

Write a program which reads n digits chosen from 0 to 9 and prints the number of combinations where the sum of the digits equals s. You can not use the same digits in a combination. For example, the combinations where n = 3 and s = 6 are as follows:

1 + 2 + 3 = 6
0 + 1 + 5 = 6
0 + 2 + 4 = 6

Input

The input consists of several datasets. Each dataset includes n (1 ≤ n ≤ 9) and s (0 ≤ s ≤ 100) separated by a space.

The input ends with a case where n = 0 and s = 0.

Output

For each dataset, print the number of combination in a line.

Sample Input

3 6
3 1
0 0

Output for the Sample Input

3
0

Source: PC Koshien 2004 , All-Japan High School Programming Contest, Aizu-Wakamatsu, Japan, 2004
http://www.pref.fukushima.jp/pc-concours/