import unittest

class TestSolution(unittest.TestCase):
    def test_simple(self):
        test_cases = [
            (0, 0),     # Base case: n = 0
            (1, 1),     # Base case: n = 1
            (2, 1),     # Fibonacci(2) = 1
            (3, 2),     # Fibonacci(3) = 2
            (5, 5),     # Fibonacci(5) = 5
            (9, 34),    # Fibonacci(9) = 34
        ]
        
        print("\n=== Function Output Test Results ===")
        for input_val, expected in test_cases:
            try:
                actual = fibonacci(input_val)  # pyright: ignore[reportUndefinedVariable]
                status = "✓ PASS" if actual == expected else "✗ FAIL"
                print(f"{status} | Input: {input_val} -> Got: {actual} | Expected: {expected}")
                self.assertEqual(actual, expected)
            except Exception as e:
                print(f"✗ ERROR | Input: {input_val} -> Exception: {e}")
                raise

if __name__ == "__main__":
    unittest.main(verbosity=2)

"""
def fibonacci(n):
    a = 0
    b = 1
    
    # Check if n is less than 0
    if n < 0:
        print("Incorrect input")
        
    # Check if n is equal to 0
    elif n == 0:
        return 0
      
    # Check if n is equal to 1
    elif n == 1:
        return b
    else:
        for i in range(1, n):
            c = a + b
            a = b
            b = c
        return b

print(fibonacci(9))
"""