【python】中文数字转换为阿拉伯数字

题目：中文数字转换为阿拉伯数字，如下：

输入：

十一万亿五千三百万三千二百零七

输出：

11000053003207

思路：

1. 先写一个处理10000以下的转换函数，如下代码的 num_process()
1. 以亿和万分别进行切分，如下代码的yi_wan_process()

num_map = {'零': 0, '一': 1, '二': 2, '三': 3, '四': 4, '五': 5, '六': 6, '七': 7, '八': 8, '九': 9}

unit_map = {'十': 10, '百': 100, '千': 1000, '万': 10000, '亿': 100000000}


# 处理 一万 以下的情况
def num_process(chinese_number):
    if not chinese_number:
        return 0

    result = 0
    first_unit = chinese_number[0] in unit_map
    num = 0
    for index, char in enumerate(chinese_number):
        if char in num_map:
            num = num_map[char]
            if index == len(chinese_number) - 1:
                result += num
        elif char in unit_map:
            if index == 0 and first_unit:
                result += unit_map[char]
            else:
                result += num * unit_map[char]
            num = 0
    return result


# 以 亿 和 万 进行切分
def yi_wan_process(chinese_number, split_unit):
    if not chinese_number:
        return 0

    result = 0
    before, after = "", chinese_number
    index = chinese_number.find(split_unit)
    if index != -1:
        before = chinese_number[:index]
        after = chinese_number[index + 1:]
    if split_unit == "亿":
        result += yi_wan_process(before, "万") * unit_map[split_unit]
        result += yi_wan_process(after, "万")
    elif split_unit == "万":
        result += num_process(before) * unit_map[split_unit]
        result += num_process(after)
    return result


def chinese_to_arabic(chinese_number):
    if not chinese_number:
        return 0
    return yi_wan_process(chinese_number, "亿")


if __name__ == "__main__":
    chinese_number = "十一万亿五千三百万三千二百零七"
    result = chinese_to_arabic(chinese_number)
    print(chinese_number, result)	# 十一万亿五千三百万三千二百零七 11000053003207