如何计算字符串中的单词数

def count_words(string):
    # 将字符串按照空格进行分割，得到一个单词数组
    words = string.split(" ")
    
    count = 0
    for word in words:
        # 统计非空单词的数量
        if word != "":
            count += 1
    
    return count

# 测试
string = "Hello world! This is a sample string."
word_count = count_words(string)
print("单词数：", word_count)