add: num of 1 bit

Author: Yongseok-Choi-dev

number-of-1-bits/YoungSeok-Choi.java

@@ -0,0 +1,16 @@
+// NOTE: 10진수를 2 진수로 변환
+// O(logN)
+class Solution {
+    public int hammingWeight(int n) {
+        int oneCnt = 0;
+
+        while(n >= 1) {
+            if((n % 2) == 1) {
+                oneCnt++;
+            }
+            n = n / 2;
+        }
+        
+        return oneCnt;
+    }
+}