151. 翻转字符串里的单词

class Solution:
    def reverseWords(self, s: str) -> str:
        s=s.split()
        s=" ".join(s[::-1])
        return s
        # 使用API
# 自己编写
class Solution:
    def reverseWords(self, s: str) -> str:
        result=[]
        if not s:
            return ""
        flag=0 if s[0]==" " else 1
        total=""
        for i in s:
            if i!=" ":
                
                total+=i
                flag=1
                continue
            if i==" " and flag==1:
                result.append(total+" ")
                total=""
                flag=0
                continue
        if total and total[0]!=" ":
            result.append(total+" ")
        total=""
        for i in result:
            total=i+total
        return total[:-1]