import random
import unittest
from sparse_table import SparseTable


class TestSparseTable(unittest.TestCase):
    def test_min_basic(self):
        a = [3, 1, 4, 1, 5, 9, 2, 6]
        st = SparseTable(a)
        self.assertEqual(st.query(0, 7), 1)
        self.assertEqual(st.query(1, 4), 1)
        self.assertEqual(st.query(2, 5), 1)
        self.assertEqual(st.query(6, 7), 2)

    def test_single(self):
        st = SparseTable([42])
        self.assertEqual(st.query(0, 0), 42)

    def test_empty_raises(self):
        st = SparseTable([])
        with self.assertRaises(IndexError):
            st.query(0, 0)

    def test_invalid_range(self):
        st = SparseTable([1, 2, 3])
        for l, r in [(-1, 1), (0, 3), (2, 1)]:
            with self.assertRaises(IndexError):
                st.query(l, r)

    def test_max_func(self):
        a = [3, 1, 4, 1, 5, 9, 2, 6]
        st = SparseTable(a, func=max)
        self.assertEqual(st.query(0, 7), 9)
        self.assertEqual(st.query(1, 4), 5)

    def test_gcd_func(self):
        import math
        a = [12, 18, 24, 30]
        st = SparseTable(a, func=math.gcd)
        self.assertEqual(st.query(0, 3), 6)
        self.assertEqual(st.query(1, 2), 6)

    def test_fuzz_min(self):
        rng = random.Random(7)
        for _ in range(200):
            n = rng.randint(1, 60)
            a = [rng.randint(-100, 100) for _ in range(n)]
            st = SparseTable(a)
            for _ in range(50):
                l = rng.randrange(n)
                r = rng.randrange(l, n)
                self.assertEqual(st.query(l, r), min(a[l:r + 1]))

    def test_fuzz_max(self):
        rng = random.Random(9)
        for _ in range(100):
            n = rng.randint(1, 40)
            a = [rng.randint(-50, 50) for _ in range(n)]
            st = SparseTable(a, func=max)
            for _ in range(30):
                l = rng.randrange(n)
                r = rng.randrange(l, n)
                self.assertEqual(st.query(l, r), max(a[l:r + 1]))


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