It only stated the first, second, third, and last round. Should be updated as follows:
There are n bulbs that are initially off. You first turn on all the bulbs. Then, you turn off every second bulb. On the third round, you toggle every third bulb (turning on if it's off or turning off if it's on). For the ith round, you toggle every i bulb. For the nth round, you only toggle the last bulb. Find how many bulbs are on after n rounds.
Looks like your connection to LeetCode Discuss was lost, please wait while we try to reconnect.