from collections import Counter

from utils.Url import Url


def count_string():
    with open('string.txt') as file:
        string = file.read()
        return Counter(string)


def get_lowest(counted_dict):
    lowest_string = ''
    for key in counted_dict:
        if counted_dict[key] == 1:
            lowest_string += key
    return lowest_string


def main():
    counted = count_string()
    lowest_string = get_lowest(counted)
    builder = Url()
    builder.solution = lowest_string
    print(builder.url)


if __name__ == '__main__':
    main()