Bonus task $(5$ points$)$: However, if we directly use the modification of our subset codes, there would be an issue, which will cause your codes to be very slow. Can you point it out?

Hint: Draw the tree of recursive calls for the following input and then you will see the issue:$)$ nums $=\{1,1,1,1,1,1,1,1,1,1,1,1\}($i$.$e$.,12$ ones$).$