如何找到从s1到s2的最小可能周期偏移？

def compute_lps(pattern):
    length = 0  # length of the previous longest prefix suffix
    lps = [0] * len(pattern)
    i = 1
    while i < len(pattern):
        if pattern[i] == pattern[length]:
            length += 1
            lps[i] = length
            i += 1
        else:
            if length != 0:
                length = lps[length - 1]
            else:
                lps[i] = 0
                i += 1
    return lps

def kmp_search(text, pattern):
    lps = compute_lps(pattern)
    i = j = 0
    while i < len(text):
        if pattern[j] == text[i]:
            i += 1
            j += 1
        if j == len(pattern):
            return i - j
        elif i < len(text) and pattern[j] != text[i]:
            if j != 0:
                j = lps[j - 1]
            else:
                i += 1
    return -1

def find_min_period_shift(s1, s2):
    if len(s2) % len(s1) != 0:
        return -1  # s2 is not a substring of any period of s1
    period = len(s2) // len(s1)
    extended_s1 = (s1 * period)
    offset = kmp_search(extended_s1, s2)
    if offset == -1:
        return -1  # s2 is not found in the extended s1
    return offset // len(s1)

# Example usage:
s1 = "abc"
s2 = "abcabc"
print(find_min_period_shift(s1, s2))  # Output should be 1