You have n bulbs in a row numbered from 1 to n. Initially, all the bulbs are turned off. We turn on exactly one bulb every day until all bulbs are on after n days. You are given an array bulbs of length n where bulbs[i] = x means that on the (i+1)th day, we will turn on the bulb at position x where i is 0-indexed and x is 1-indexed. Given an integer k, return the minimum day number such that there exists two turned on bulbs that have exactly k bulbs between them that are all turned off. If there isn't such day, return -1. Example 1: Input: bulbs = [1,3,2], k = 1 Output: 2 Explanation: On the first day: bulbs[0] = 1, first bulb is turned on: [1,0,0] On the second day: bulbs[1] = 3, third bulb is turned on: [1,0,1] On the third day: bulbs[2] = 2, second bulb is turned on: [1,1,1] We return 2 because on the second day, there were two on bulbs with one off bulb between them. Example 2: Input: bulbs = [1,2,3], k = 1 Output: -1 Constraints: n == bulbs.length 1 <= n <= 2 * 104 1 <= bulbs[i] <= n bulbs is a permutation of numbers from 1 to n. 0 <= k <= 2 * 104