Задание 24. Информатика. ЕГЭ. Поляков-7223

Python. Два указателя

s = open('7193.txt').readline().strip()
alph = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
p_char = {c: []  for c in alph}
count_char = {c: 0 for c in alph}
ml = 0
p_begin = 0

for p in range(len(s)):
    if s[p] in alph:
        p_char[s[p]].append(p)
        count_char[s[p]] += 1

        if any(count_char[c] > 1 for c in alph):
            stmp = [c for c in alph if c != s[p]]
            ml = max(ml, p - p_begin)
            p_begin = p_char[s[p]].pop(0) + 1
            count_char[s[p]] -= 1
            for c in stmp:
                p_char[c] = [t for t in p_char[c] if t >= p_begin]
                count_char[c] = len(p_char[c])

ml = max(ml, len(s) - p_begin)
print(ml)

Ответ: \(23\)