CDE

Task/Evaluate-binomial-coefficients/Python/evaluate-binomial-coefficients-1.py

@@ -0,0 +1,8 @@
+def binomialCoeff(n, k):
+    result = 1
+    for i in range(1, k+1):
+        result = result * (n-i+1) / i
+    return result
+
+if __name__ == "__main__":
+    print(binomialCoeff(5, 3))

Task/Evaluate-binomial-coefficients/Python/evaluate-binomial-coefficients-2.py

@@ -0,0 +1,17 @@
+from operator import mul
+def comb(n,r):
+    ''' calculate nCr - the binomial coefficient
+    >>> comb(3,2)
+    3
+    >>> comb(9,4)
+    126
+    >>> comb(9,6)
+    84
+    >>> comb(20,14)
+    38760
+    '''
+
+    if r > n-r:  # for smaller intermediate values
+        r = n-r
+    return int( reduce( mul, range((n-r+1), n+1), 1) /
+      reduce( mul, range(1,r+1), 1) )