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snippets/gcd.md

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+### gcd
+
+Calculates the greatest common divisor between two or more numbers/arrays.
+
+The `helperGcdfunction` uses recursion. Base case is when `y` equals `0`. In this case, return `x`. Otherwise, return the GCD of `y` and the remainder of the division `x/y`.
+
+Uses the reduce function from the inbuild module `functools`. Also defines a method `spread` for javascript like spreading of arrays.
+
+``` python
+    from functools import reduce
+	def spread(arg):
+         ret = []
+         for i in arg:
+           if isinstance(i,list):
+             ret.extend(i)
+           else:
+             ret.append(i)
+         return ret
+    def gcd(*args):
+        numbers = []
+        numbers.extend(spread(list(args)))
+        def helperGcd(x,y):
+            return x if not y else gcd(y,x%y)
+        return reduce((lambda x,y : helperGcd(x,y)),numbers)
+```