diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ed8ebf5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+__pycache__
\ No newline at end of file
diff --git a/tests/test_automata.py b/tests/test_automata.py
index dbd766a..dff027b 100644
--- a/tests/test_automata.py
+++ b/tests/test_automata.py
@@ -1,10 +1,22 @@
 from algorithms.automata import DFA
 
 
+import unittest
 import unittest
 
 
 class TestDFA(unittest.TestCase):
+    def setUp(self):
+        # DFA transitions table example
+        self.transitions = {
+            'q0': {'a': 'q1', 'b': None},
+            'q1': {'a': 'q1', 'b': 'q2'},
+            'q2': {'a': 'q1', 'b': 'q3'},
+            'q3': {'a': None, 'b': None}
+        }
+        self.start = 'q0'
+        self.final = ['q3']
+
     def test_DFA(self):
         transitions = {
             'a': {'1': 'a', '0': 'b'},
@@ -43,6 +55,31 @@ def test_DFA(self):
         self.assertEqual(False, DFA(transitions2, start2, final2, "aaabbb"))
         self.assertEqual(True, DFA(transitions2, start2, final2, "baabba"))
 
+    def test_reject_string(self):
+        # Test case where DFA should reject the string
+        string = 'aaa'
+        result = DFA(self.transitions, self.start, self.final, string)
+        self.assertFalse(result)
+
+    def test_invalid_transition(self):
+        # Test case where DFA encounters an invalid transition
+        string = 'b'
+        result = DFA(self.transitions, self.start, self.final, string)
+        self.assertFalse(result)
+
+    def test_empty_string(self):
+        # Test case where the string is empty, start state is not a final state
+        string = ''
+        result = DFA(self.transitions, self.start, self.final, string)
+        self.assertFalse(result)
+
+    def test_empty_string_with_final_start(self):
+        # Test case where the string is empty and start state is a final state
+        str = 'aab'
+        start_final = ['q0']
+        result = DFA(self.transitions, self.start, start_final, '')
+        self.assertTrue(result)
+
 
 if __name__ == '__main__':
     unittest.main()