在列表中查找出现次数最多的子串

def find_most_common_substring(lst):
    substring_count = {}
    
    # 遍历列表中的每个字符串
    for string in lst:
        # 将每个字符串拆分为子串
        for i in range(len(string)):
            for j in range(i+1, len(string)+1):
                substring = string[i:j]
                
                # 更新子串出现次数
                if substring in substring_count:
                    substring_count[substring] += 1
                else:
                    substring_count[substring] = 1
    
    # 找到出现次数最多的子串及其出现次数
    max_count = 0
    max_substring = ""
    for substring, count in substring_count.items():
        if count > max_count:
            max_count = count
            max_substring = substring
    
    return max_substring

# 示例用法
lst = ["abc", "bcd", "abcd", "abc", "bcd", "abcd", "abc"]
result = find_most_common_substring(lst)
print("出现次数最多的子串是:", result)