题目描述
Write a program that extracts n different numbers from the numbers 0 to 9 and outputs the number of combinations that add up to s. Each n number is from 0 to 9, and the same number cannot be used in one combination. For example, if n is 3 and s is 6, the combination of the three numbers totaling 6 is
1 + 2 + 3 = 6
0 + 1 + 5 = 6
0 + 2 + 4 = 6
There are three ways.
Input
Given multiple datasets. For each dataset, n (1 ≤ n ≤ 9) and s (0 ≤ s ≤ 100) are given on one line, separated by a single space. When both n and s are 0, it is the end of the input (in this case, the program is terminated without processing).
The number of datasets does not exceed 50.
Output
For each dataset, output the number of combinations in which the sum of n integers is s on one line.
Example
Input
3 6
3 1
0 0
Output
3
0
输入格式
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输出格式
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