Create prime factorisation exercise

17_prime_factors.lua

@@ -0,0 +1,50 @@
+-- Write a function which determines the prime factors of a given
+-- number, returning them in a list.  You may assume that none of the
+-- prime factors are above 10000
+--
+-- Solution --------------------------------------------------------------------
+function prime_factors(n)
+	-- Your implementation here
+end
+
+-- Tests -----------------------------------------------------------------------
+
+local luaunit = require("luaunit.luaunit")
+
+function test_prime_factors_of_42()
+	luaunit.assertItemsEquals(prime_factors(42), {2, 3, 7})
+end
+
+function test_prime_factors_of_70()
+	luaunit.assertItemsEquals(prime_factors(70), {2, 5, 7})
+end
+
+function test_prime_factors_of_253()
+	luaunit.assertItemsEquals(prime_factors(253), {11, 23})
+end
+
+function test_prime_factors_of_245()
+	luaunit.assertItemsEquals(prime_factors(245), {5, 7, 7})
+end
+
+function test_prime_factors_of_36()
+	luaunit.assertItemsEquals(prime_factors(36), {2, 2, 3, 3})
+end
+
+function test_prime_factors_of_1337()
+	luaunit.assertItemsEquals(prime_factors(1337), {7, 191})
+end
+
+function test_prime_factors_of_4321()
+	luaunit.assertItemsEquals(prime_factors(4321), {29, 149})
+end
+
+function test_prime_factors_of_57812834()
+	luaunit.assertItemsEquals(prime_factors(57812834), {2, 29, 113, 8821})
+end
+
+function test_prime_factors_of_8894220()
+	luaunit.assertItemsEquals(prime_factors(8894220), {2, 2, 3, 5, 271, 547})
+end
+
+os.exit(luaunit.LuaUnit.run())