将文件拆分为更小的最多n个字符的文件，而不剪切任何行

def split_file(filename, n):
    with open(filename, 'r') as file:
        content = file.read()
    
    split_content = ''
    file_count = 1
    
    for char in content:
        split_content += char
        
        if len(split_content) >= n:
            save_file(split_content, filename, file_count)
            split_content = ''
            file_count += 1
    
    if split_content:
        save_file(split_content, filename, file_count)

def save_file(content, original_filename, file_count):
    new_filename = f"{original_filename}_part{file_count}"
    
    with open(new_filename, 'w') as file:
        file.write(content)

# 示例用法
split_file('example.txt', 100)