You are given an integer array nums of length n.
You start at index 0, and your goal is to reach index n - 1.
From any index i, you may perform one of the following operations:
i + 1 or i - 1, if the index is within bounds.nums[i] is a prime number p, you may instantly jump to any index j != i such that nums[j] % p == 0.Return the minimum number of jumps required to reach index n - 1.
Example 1:
Input: nums = [1,2,4,6]
Output: 2
Explanation:
One optimal sequence of jumps is:
i = 0. Take an adjacent step to index 1.i = 1, nums[1] = 2 is a prime number. Therefore, we teleport to index i = 3 as nums[3] = 6 is divisible by 2.Thus, the answer is 2.
Example 2:
Input: nums = [2,3,4,7,9]
Output: 2
Explanation:
One optimal sequence of jumps is:
i = 0. Take an adjacent step to index i = 1.i = 1, nums[1] = 3 is a prime number. Therefore, we teleport to index i = 4 since nums[4] = 9 is divisible by 3.Thus, the answer is 2.
Example 3:
Input: nums = [4,6,5,8]
Output: 3
Explanation:
0 → 1 → 2 → 3. Thus, the answer is 3.Constraints:
1 <= n == nums.length <= 1051 <= nums[i] <= 106nums[i] via a sieve, and build a bucket bucket[p] mapping each prime p to all indices j with nums[j] % p == 0.i, enqueue its adjacent steps (i+1 and i-1) and all indices in bucket[p] for each prime p dividing nums[i], then clear bucket[p] so each prime's bucket is visited only once.[1,2,4,6]
[2,3,4,7,9]
[4,6,5,8]