number of 1 bits solution

Author: bhan

number-of-1-bits/byol-han.js

@@ -0,0 +1,30 @@
+/**
+ * @param {number} n
+ * @return {number}
+ */
+//1. divide the number by 2 and count the remainder
+var hammingWeight = function (n) {
+  let count = 0;
+  while (n > 0) {
+    if (n % 2 === 1) {
+      count++;
+    }
+    n = Math.floor(n / 2);
+  }
+  return count;
+};
+
+//2. Count the number of set bits (1s) in the binary representation of n
+var hammingWeight = function (n) {
+  return n.toString(2).split("1").length - 1;
+};
+
+//3. bit manipulation
+var hammingWeight = function (n) {
+  let count = 0;
+  while (n > 0) {
+    count += n & 1; // 마지막 비트가 1이면 count++
+    n = n >>> 1; // 오른쪽으로 한 비트 이동 (2로 나눔)
+  }
+  return count;
+};