Swap For Longest Repeated Character Substring

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class Solution:
    def maxRepOpt1(self, text: str) -> int:
        idx = [[] for _ in range(26)]
        res = 1

        # Store indices of each character in idx
        for i in range(len(text)):
            idx[ord(text[i]) - ord('a')].append(i)

        # Iterate through all characters from 'a' to 'z'
        for n in range(26):
            cnt = 1
            cnt1 = 0
            mx = 0
            for i in range(1, len(idx[n])):
                if idx[n][i] == idx[n][i - 1] + 1:
                    cnt += 1
                else:
                    cnt1 = cnt if idx[n][i] == idx[n][i - 1] + 2 else 0
                    cnt = 1
                mx = max(mx, cnt1 + cnt)

            res = max(res, mx + (1 if len(idx[n]) > mx else 0))

        return res