查找字符串中的最后一个或第一个句点，并添加周数字

def add_week_number(string, week_number):
    last_dot_index = string.rfind('.')
    if last_dot_index != -1:
        return string[:last_dot_index+1] + str(week_number) + string[last_dot_index+1:]
    else:
        return string + str(week_number)

# 示例用法
string = "这是一个示例句子。"
week_number = 42
result = add_week_number(string, week_number)
print(result)

这是一个示例句子。42

def add_week_number(string, week_number):
    first_dot_index = string.find('.')
    if first_dot_index != -1:
        return string[:first_dot_index+1] + str(week_number) + string[first_dot_index+1:]
    else:
        return string + str(week_number)

# 示例用法
string = "这是一个示例句子。"
week_number = 42
result = add_week_number(string, week_number)
print(result)

这是一个示例句子。42