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Task/Factorial/Sidef/factorial.sidef

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+# Recursive
+func factorial_recursive(n) {
+    n == 0 ? 1 : (n * __FUNC__(n-1));
+}
+
+# Iterative with Array#reduce
+func factorial_reduce(n) {
+    1..n -> reduce('*');
+}
+
+# Iterative with Block#repeat
+func factorial_iterative(n) {
+    var f = 1;
+    {|i| f *= i } * n;
+    return f;
+}
+
+# Built-in Number#factorial:
+say 5!;