Update Counting Bits.js

When i === pow, pow doubles;
For next iteration, i is smaller than pow. That will be the issue if i is less than pow for ELSE condition.
So added another variable copyOfPow (old pow) to manage the scenario when copyOfPow < i < pow.

Author: superdtx

Counting Bits.js

@@ -18,16 +18,18 @@
 var countBits = function(num) {
     var result = [],
         pow = 1,
+        copyOfPow = 1,
         i;
 
     result[0] = 0;
 
-    for (i = 1; i < num; i++) {
+    for (i = 1; i <= num; i++) {
         if (i === pow) {
             result[i] = 1;
+            copyOfPow = pow;
             pow *= 2;
         } else {
-            result[i] = result[pow] + result[i - pow];
+            result[i] = result[copyOfPow] + result[i - copyOfPow];
         }
     }