Задание 24. Информатика. ЕГЭ. Поляков-8125

Python

from re import finditer

s = open('8120.txt').readline().strip()
nums = []
ml = 0

for g in finditer(r'[1-9A-D][0-9A-D]+', s):
    if len(g.group(0)) < ml:
        continue
    ts = g.group(0)
    len_ts = len(ts)
    pref = [0] * len_ts
    pref[0] = int(ts[0], 14) % 5
    for i in range(1, len_ts):
        pref[i] = (pref[i-1] + (-1)**i * int(ts[i], 14)) % 5 #14**1 % 5 = 1 если i чётное, и = -1, если i нечётное 
    if pref[-1] == 0:
        nums.append(ts)
        ml = len_ts
    else:
        s_tmp = set()
        for k in range(len_ts - ml):
            if ts[k] not in s_tmp:
                s_tmp.add(ts[k])
                for p in range(len_ts - 1, ml + k, -1):
                    if pref[p] == pref[k]:
                        ml = max(ml, p - k)
                        nums.append(ts[k+1:p+1])
                        break
m = max(len(d) for d in nums)
nums = sorted([d for d in nums if len(d) == m])
print(s.find(nums[-1]))

Ответ: \(13273\)