El Dorado
Description
Bruce Force has gone to Las Vegas, the El Dorado for gamblers. He is interested especially in one betting game, where a machine forms a sequence of n numbers by drawing random numbers. Each player should estimate beforehand, how many increasing subsequences of length k will exist in the sequence of numbers.
A subsequence of a sequence a[1], ..., a[n] is defined as a[i[1]], ..., a[i[m]], where 1 ≤ i[1] < i[2] < ... < i[m] ≤ n. The subsequence is increasing, if a[i[j-1]] < a[i[j]] for all 1 < j ≤ m.
Bruce doesn't trust the Casino to count the number of increasing subsequences of length k correctly. He has asked you if you can solve this problem for him.
Input
The input contains several test cases. The first line of each test case contains two numbers n and k (1 ≤ k ≤ n ≤ 100), where n is the length of the sequence drawn by the machine, and k is the desired length of the increasing subsequences. The following line contains n pairwise distinct integers ai (-10000 ≤ a[i] ≤ 10000 ), where ai is the i-th number in the sequence drawn by the machine.
The last test case is followed by a line containing two zeros.
Output
For each test case, print one line with the number of increasing subsequences of length k that the input sequence contains. You may assume that the inputs are chosen in such a way that this number fits into a 64 bit signed integer.
Sample
Input
10 5
1 2 3 4 5 6 7 8 9 10
3 2
3 2 1
0 0
Output
252
0
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