python __detect连续重复字符串

def find_longest_repeated_substring(s):
    n = len(s)
    longest = ""
    for i in range(n):
        for j in range(i + 1, n):
            # 找到两个相同字符的位置
            if s[i] == s[j]:
                length = 1
                while (j + length < n and s[i + length] == s[j + length]):
                    length += 1
                if length > len(longest):
                    longest = s[i:i + length]
    return longest

# 示例
s = "abracadabra"
print(find_longest_repeated_substring(s))  # 输出: "abra"

def compute_prefix_function(pattern):
    m = len(pattern)
    pi = [0] * m
    k = 0
    for q in range(1, m):
        while k > 0 and pattern[k] != pattern[q]:
            k = pi[k - 1]
        if pattern[k] == pattern[q]:
            k += 1
        pi[q] = k
    return pi

def kmp_search(text, pattern):
    n = len(text)
    m = len(pattern)
    pi = compute_prefix_function(pattern)
    q = 0
    for i in range(n):
        while q > 0 and pattern[q] != text[i]:
            q = pi[q - 1]
        if pattern[q] == text[i]:
            q += 1
        if q == m:
            print(f"Pattern occurs with shift {i - m + 1}")
            q = pi[q - 1]

# 示例
text = "abxabcabcaby"
pattern = "abcaby"
kmp_search(text, pattern)