查找多个字符串中的字符

def brute_force_search(text, pattern):
    n = len(text)
    m = len(pattern)
    for i in range(n - m + 1):
        if text[i:i + m] == pattern:
            return i
    return -1

def kmp_search(text, pattern):
    def compute_prefix_function(p):
        m = len(p)
        pi = [0] * m
        j = 0
        for i in range(1, m):
            while j > 0 and p[j] != p[i]:
                j = pi[j - 1]
            if p[j] == p[i]:
                j += 1
            pi[i] = j
        return pi

    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:
            return i - m + 1
    return -1

# 示例用法
text = "ABABDABACDABABCABAB"
pattern = "ABABCABAB"
print("暴力搜索结果:", brute_force_search(text, pattern))
print("KMP搜索结果:", kmp_search(text, pattern))