Data commit

Task/Evaluate-binomial-coefficients/Groovy/evaluate-binomial-coefficients-1.groovy

@@ -0,0 +1,10 @@
+def factorial = { x ->
+    assert x > -1
+    x == 0 ? 1 : (1..x).inject(1G) { BigInteger product, BigInteger factor -> product *= factor }
+}
+
+def combinations = { n, k ->
+    assert k >= 0
+    assert n >= k
+    factorial(n).intdiv(factorial(k)*factorial(n-k))
+}

Task/Evaluate-binomial-coefficients/Groovy/evaluate-binomial-coefficients-2.groovy

@@ -0,0 +1,4 @@
+assert combinations(20, 0) == combinations(20, 20)
+assert combinations(20, 10) == (combinations(19, 9) + combinations(19, 10))
+assert combinations(5, 3) == 10
+println combinations(5, 3)