From 4d370842c45713f9e71a665a89918c43d8d3b035 Mon Sep 17 00:00:00 2001
From: Wenru Dong <dongwenru.aaron.shenyang@gmail.com>
Date: Tue, 8 Jan 2019 20:44:21 +0000
Subject: [PATCH] bitmap in python

---
 python/45_bitmap/bitmap.py | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 python/45_bitmap/bitmap.py

diff --git a/python/45_bitmap/bitmap.py b/python/45_bitmap/bitmap.py
new file mode 100644
index 0000000..1022b74
--- /dev/null
+++ b/python/45_bitmap/bitmap.py
@@ -0,0 +1,30 @@
+"""
+    Author: Wenru Dong
+"""
+
+from typing import Optional
+
+class Bitmap:
+    def __init__(self, num_bits: int):
+        self._num_bits = num_bits
+        self._bytes = bytearray(num_bits // 8 + 1)
+    
+    def setbit(self, k: int) -> None:
+        if k > self._num_bits or k < 1: return
+        self._bytes[k // 8] |= (1 << k % 8)
+    
+    def getbit(self, k: int) -> Optional[bool]:
+        if k > self._num_bits or k < 1: return
+        return self._bytes[k // 8] & (1 << k % 8) != 0
+
+
+if __name__ == "__main__":
+    bitmap = Bitmap(10)
+    bitmap.setbit(1)
+    bitmap.setbit(3)
+    bitmap.setbit(6)
+    bitmap.setbit(7)
+    bitmap.setbit(8)
+
+    for i in range(1, 11):
+        print(bitmap.getbit(i))
\ No newline at end of file