Package g0901_1000.s0995_minimum_number_of_k_consecutive_bit_flips

Class Solution

java.lang.Object
g0901_1000.s0995_minimum_number_of_k_consecutive_bit_flips.Solution
public class Solution extends java.lang.Object
995 - Minimum Number of K Consecutive Bit Flips.

Hard

You are given a binary array nums and an integer k.

A k-bit flip is choosing a subarray of length k from nums and simultaneously changing every 0 in the subarray to 1, and every 1 in the subarray to 0.

Return the minimum number of k-bit flips required so that there is no 0 in the array. If it is not possible, return -1.

A subarray is a contiguous part of an array.

Example 1:

Input: nums = [0,1,0], k = 1

Output: 2

Explanation: Flip nums[0], then flip nums[2].

Example 2:

Input: nums = [1,1,0], k = 2

Output: -1

Explanation: No matter how we flip subarrays of size 2, we cannot make the array become [1,1,1].

Example 3:

Input: nums = [0,0,0,1,0,1,1,0], k = 3

Output: 3

Explanation:

Flip nums[0],nums[1],nums[2]: nums becomes [1,1,1,1,0,1,1,0]

Flip nums[4],nums[5],nums[6]: nums becomes [1,1,1,1,1,0,0,0]

Flip nums[5],nums[6],nums[7]: nums becomes [1,1,1,1,1,1,1,1]

Constraints:

  • 1 <= nums.length <= 105
  • 1 <= k <= nums.length

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    minKBitFlips(int[] nums, int k)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • minKBitFlips

      public int minKBitFlips(int[] nums, int k)