solve: counting bits

Author: heozeop

counting-bits/heozeop.cpp

@@ -0,0 +1,31 @@
+// Time Complexity: O(n^2)
+// Spatial Complexity: O(n)
+
+class Solution {
+private:
+    int count1(int n) {
+        int ans = 0;
+  
+        while(n) {
+            if (n % 2) {
+                ++ans;
+            }
+
+            n /= 2;
+        }
+
+        return ans;
+    }
+
+public:
+    vector<int> countBits(int n) {
+        vector<int> ans(n + 1);
+
+        for(int i = 0; i <= n; ++i) {
+            ans[i] = this->count1(i);
+        }
+
+        return ans;
+    }
+};
+