# Write a function to count those characters which have vowels as their neighbors in the given string.
def count_vowels(test_str):
    res = 0
    vow_list = ["a", "e", "i", "o", "u"]
    for idx in range(1, len(test_str) - 1):
        if test_str[idx] not in vow_list and (
            test_str[idx - 1] in vow_list or test_str[idx + 1] in vow_list
        ):
            res += 1
    if test_str[0] not in vow_list and test_str[1] in vow_list:
        res += 1
    if test_str[-1] not in vow_list and test_str[-2] in vow_list:
        res += 1
    return res
