def mid(values: list[str]):
    return values[len(values)//2]

rules,updates = {}, []
with open('sample.data') as data:
    for line in data:
        if '|' in line:
            left, right  = [int(i) for i in line.split('|')]
            if left in rules:
                rules[left].append(right)
            else:
                rules[left] = [right]
        if ',' in line:
            updates.append([int(i) for i in line.split(',')])