problem

Given an binary array nums and an integer k, return true if all 1's are at least k places away from each other, otherwise return false.

 

Example 1:

Input: nums = [1,0,0,0,1,0,0,1], k = 2
Output: true
Explanation: Each of the 1s are at least 2 places away from each other.

Example 2:

Input: nums = [1,0,0,1,0,1], k = 2
Output: false
Explanation: The second 1 and third 1 are only one apart from each other.

 

Constraints:

  • 1 <= nums.length <= 105
  • 0 <= k <= nums.length
  • nums[i] is 0 or 1

submission

impl Solution {
    pub fn k_length_apart(nums: Vec<i32>, k: i32) -> bool {
        nums.split(|&n| n == 1)
            .skip(1) // skip the first split
            .fold((true, true), |(p, n), v| {
                // tricky way to skip the last split
                (n, n && v.len() as i32 >= k)
            })
            .0
    }
}