anagram_challenge

def dict_adder(j_dict,j_char):
    """Adds an element to the dict in pos parameter 1
       from the character that is provided in pos parameter 2"""
    if j_dict.has_key(j_char):
        j_dict[j_char] += 1
    else:
        j_dict[j_char] = 1

def number_needed(a, b):
    answer = 0
    a_set = set(a)
    b_set = set(b)
    a_dict, b_dict = {}, {}
    map(lambda x: dict_adder(a_dict,x), a)
    map(lambda x: dict_adder(b_dict,x), b)
    diff_set_a = a_set.difference(b_set)
    diff_set_b = b_set.difference(a_set)
    intersection_set_a = a_set.intersection(b_set)
    if diff_set_a is not None:
        answer += sum([ a_dict[j] for j in diff_set_a])
    if diff_set_b is not None:
        answer += sum([ b_dict[j] for j in diff_set_b])
    for j in intersection_set_a:
        if a_dict[j] > b_dict[j]:
            answer += a_dict[j] - b_dict[j]
        elif a_dict[j] < b_dict[j]:
            answer += b_dict[j] - a_dict[j]
    return answer



a = raw_input().strip()
b = raw_input().strip()

print number_needed(a, b)