字符串反转
def reverseString(s):
begin = 0
end = len(s)-1
ss = list(s)
while(end>begin):
ss[begin], ss[end] = ss[end], ss[begin]
end -= 1
begin += 1
return ''.join(ss)
def reverseString(s):
begin = 0
end = len(s)-1
ss = list(s)
while(end>begin):
ss[begin], ss[end] = ss[end], ss[begin]
end -= 1
begin += 1
return ''.join(ss)