diff --git a/regexp.py b/regexp.py
--- a/regexp.py
+++ b/regexp.py
@@ -1,5 +1,6 @@
 import math
 import itertools
+import argparse
 from abc import abstractmethod
 from collections import deque
 
@@ -380,7 +381,7 @@ class RegexpDFA:
 		return (rules, end_states)
 
 
-if __name__ == "__main__":
+def test():
 	tests = ["", "a", "ab", "aabb", "abab", "abcd", "abcbcdbcd"]
 	for pattern in ["a(b|c)", "a*b*", "(ab)*", "a((bc)*d)*", "(a|b)*a(a|b)(a|b)(a|b)", "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"]:
 		print("#", pattern)
@@ -393,3 +394,30 @@ if __name__ == "__main__":
 		for t in tests:
 			print(t, r.match(t))
 		print()
+
+
+if __name__ == "__main__":
+	parser = argparse.ArgumentParser()
+	subparsers = parser.add_subparsers()
+	
+	test_parser = subparsers.add_parser("test")
+	test_parser.set_defaults(name="test")
+
+	match_parser = subparsers.add_parser("match")
+	match_parser.add_argument("pattern")
+	match_parser.add_argument("string")
+	match_parser.set_defaults(name="match")
+
+	args = parser.parse_args()
+
+	if args.name == "test":
+		test()
+	elif args.name == "match":
+		try:
+			r = RegexpDFA.create(args.pattern).reduce().normalize()
+		except ParsingError as e:
+			print("Failed to parse the regexp:")
+			print(e)
+		print(r.match(args.string))
+	else:
+		parser.print_help()
\ No newline at end of file