158. Read N Characters Given Read4 II - Call multiple times
这题做的马虎了，其实基本思路比较简单，不过做题做得有点倦。
# The read4 API is already defined for you.
# @param buf, a list of characters
# @return an integer
# def read4(buf):
class Solution(object):
def read(self, buf, n):
"""
:type buf: Destination buffer (List[str])
:type n: Maximum number of characters to read (int)
:rtype: The number of characters read (int)
"""
idx = 0
while True:
buf4 = [""]*4
l = read4(buf4)
self.queue.extend(buf4)
curr = min(len(self.queue), n-idx)
for i in xrange(curr):
buf[idx] = self.queue.pop(0)
idx+=1
if curr == 0:
break
return idx
def __init__(self):
self.queue = []
