feat: solve No.201

Author: BaffinLee

201-300/201. Bitwise AND of Numbers Range.md

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+# 201. Bitwise AND of Numbers Range
+
+- Difficulty: Medium.
+- Related Topics: Bit Manipulation.
+- Similar Questions: Longest Nice Subarray.
+
+## Problem
+
+Given two integers `left` and `right` that represent the range `[left, right]`, return **the bitwise AND of all numbers in this range, inclusive**.
+
+ 
+Example 1:
+
+```
+Input: left = 5, right = 7
+Output: 4
+```
+
+Example 2:
+
+```
+Input: left = 0, right = 0
+Output: 0
+```
+
+Example 3:
+
+```
+Input: left = 1, right = 2147483647
+Output: 0
+```
+
+ 
+**Constraints:**
+
+
+	
+- `0 <= left <= right <= 231 - 1`
+
+
+
+## Solution
+
+```javascript
+/**
+ * @param {number} left
+ * @param {number} right
+ * @return {number}
+ */
+var rangeBitwiseAnd = function(left, right) {
+    var count = 0;
+    while (left !== right) {
+        left >>= 1;
+        right >>= 1;
+        count += 1;
+    }
+    return left << count;
+};
+```
+
+**Explain:**
+
+nope.
+
+**Complexity:**
+
+* Time complexity : O(1).
+* Space complexity : O(1).