> For the complete documentation index, see [llms.txt](https://garylai.gitbook.io/algorithm-and-data-structure/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://garylai.gitbook.io/algorithm-and-data-structure/problems/other/read-n-characters-given-read4/read-n-characters-given-read4-ii-call-multiple-times.md).

# 158. Read N Characters Given Read4 II - Call multiple times

[158. Read N Characters Given Read4 II - Call multiple times](https://leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/)

```python
# The read4 API is already defined for you.
# def read4(buf4: List[str]) -> int:

class Solution:
    def __init__(self):
        self.queue = collections.deque()

    def read(self, buf, n):
        i = 0
        while i < n:
            buf4 = [''] * 4 
            _ = read4(buf4) 
            self.queue.extend(buf4)
            count = min(len(self.queue), n - i) 
            if not count:
                break
            buf[i:] = [self.queue.popleft() for _ in range(count)]
            i += count
        return i
```