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compute Binomial Coefficient or combinations with dynamic programming

The Problem
Write a function that takes two parameters n and k and returns the value of Binomial Coefficient C(n, k). For example, your function should return 6 for n = 4 and k = 2, and it should return 10 for n = 5 and k = 2.

1 def ComputeBinomialCoefficients(n,k):2     # ComputeBinomialCoefficients(5,2) shoud return 103     table = [0] * (k+1)4     table[0] = 15     for i in range(1, n+1):6         for j in range(min(i,k), 0, -1):       # why begin with min(i,k): 1) we do not need any results more than k. 2) Yang Hui (Pascal) Triangle: j must be less than i7             table[j] = table[j] + table[j - 1]   # this comes from YANG Hui Triangle (or Pascal Trianle) of Binomial Coefficients8     9     return table[k]

 

referece: 

http://www.geeksforgeeks.org/dynamic-programming-set-9-binomial-coefficient/

http://en.wikipedia.org/wiki/Pascal%27s_triangle

compute Binomial Coefficient or combinations with dynamic programming