def test_0(): assert countPairs("axa") == 1
def test_1(): assert countPairs("axax") == 2
def test_9(): assert countPairs("aa") == 0
def test_10(): assert countPairs("aaa") == 1
def test_7(): assert countPairs("") == 0
def test_8(): assert countPairs("a") == 0
def test_6(): assert countPairs("ihjxhh") == 0
def test_5(): assert countPairs("ihihhh") == 3
def test_4(): assert countPairs("hihih") == 3
def test_3(): assert countPairs("hi") == 0
def test_2(): assert countPairs("axbx") == 1