You are given n bulbs, all initially turned off. You perform n rounds of toggling operations:

• In round $1$, you turn on every bulb.

• In round $2$, you toggle every $2^{nd}$ bulb.

• In round $3$, you toggle every $3^{rd}$ bulb.

• In general, during round i, you toggle every i-th bulb (turning it on if it is off, or turning it off if it is on).

• In round n, you toggle only the last bulb.

Return the number of bulbs that remain on after all n rounds have been completed.

Constraints:

• $0 \leq$ n $\leq 10^9$

Now, let's take a moment to make sure you've correctly understood the problem. The quiz below helps you check if you're solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Implement your solution in the following coding playground.