✨ bitwise and of numbers range

Author: tangweikun

CATEGORY.md

@@ -47,6 +47,7 @@
 * 二叉搜索树
 
 - 位运算
+  201
 
 * 并查集
 

src/201-bitwise-and-of-numbers-range/index.js

@@ -0,0 +1,16 @@
+/**
+ * @param {number} m
+ * @param {number} n
+ * @return {number}
+ */
+
+//  HELP:
+
+var rangeBitwiseAnd = function (m, n) {
+  while (m < n) {
+    // 抹去最右边的 1
+    n = n & (n - 1);
+  }
+
+  return n;
+};