day10.py

def process_line(line):
    return int(line)


class DO_NOT_SPLIT:
    pass


def read_input(file_name: str,
               first_delimiter: str or None or DO_NOT_SPLIT = '\n',
               second_delimiter: str or None or DO_NOT_SPLIT=DO_NOT_SPLIT,
               third_delimiter: str or None or DO_NOT_SPLIT=DO_NOT_SPLIT,
               final_group_processor=process_line):
    with open(file_name) as f:
        processed_input = f.read()
        if first_delimiter is not DO_NOT_SPLIT:
            first_split = processed_input.split(first_delimiter)
            if second_delimiter is not DO_NOT_SPLIT:
                second_split = [x.split(second_delimiter) for x in first_split]

                if third_delimiter is not DO_NOT_SPLIT:
                    output = [[[final_group_processor(group) for group in x.split(third_delimiter)] for x in inner_split] for inner_split in second_split]
                else:
                    output = [[final_group_processor(x) for x in inner_split] for inner_split in second_split]
            else:
                output = [final_group_processor(group) for group in first_split]
        else:
            output = final_group_processor(processed_input)
    return output

class Exc(Exception):
    pass

def solvep1(input):
    diff_1 = 0
    diff_3 = 1
    input.sort()
    last = 0
    for i in input:
        if i - last == 1:
            diff_1 +=1
        elif i - last == 3:
            diff_3 += 1
        else:
            raise RuntimeError()
        last=i
    return diff_1 * diff_3


def solvep2(input):
    sums = [0] * (input[-1] +  1)
    sums [0] = 1
    for num in input:
        sums[num] += sums[num-1]
        if num >= 2:
            sums[num] += sums[num-2]
        if num >= 3:
            sums[num] += sums[num-3]
    return sums[-1]
    return input



if __name__ == '__main__':
    processed_input = read_input('day10-input.txt')
    output1 = solvep1(processed_input)
    print(output1)
    output2 = solvep2(processed_input)
    print(output2)