Add solution #191

Author: JoshCrozier

README.md

@@ -56,6 +56,7 @@
 151|[Reverse Words in a String](./0151-reverse-words-in-a-string.js)|Medium|
 152|[Maximum Product Subarray](./0152-maximum-product-subarray.js)|Medium|
 179|[Largest Number](./0179-largest-number.js)|Medium|
+191|[Number of 1 Bits](./0191-number-of-1-bits.js)|Easy|
 203|[Remove Linked List Elements](./0203-remove-linked-list-elements.js)|Easy|
 206|[Reverse Linked List](./0206-reverse-linked-list.js)|Easy|
 217|[Contains Duplicate](./0217-contains-duplicate.js)|Easy|

solutions/0191-number-of-1-bits.js

@@ -0,0 +1,16 @@
+/**
+ * 191. Number of 1 Bits
+ * https://leetcode.com/problems/number-of-1-bits/
+ * Difficulty: Easy
+ *
+ * Write a function that takes an unsigned integer and returns the number of
+ * '1' bits it has (also known as the Hamming weight).
+ */
+
+/**
+ * @param {number} n - a positive integer
+ * @return {number}
+ */
+var hammingWeight = function(n) {
+  return n.toString(2).match(/1/g)?.length || 0;
+};