public class DayCode {    public static void main(String[] args) {        int[] A = new int[]{0, 1, 0};        int K = 1;        int ans = new DayCode().minKBitFlips(A, K);        System.out.println("ans is " + ans);    }
    /**     * https://leetcode-cn.com/problems/minimum-number-of-k-consecutive-bit-flips/     * 时间复杂度O(n * k),空间复杂度O(1)     * @param A     * @param K     * @return     */    public int minKBitFlips(int[] A, int K) {        int ans = 0;        int n = A.length;        for (int i = 0; i < n; i++) {            if (A[i] == 0) {                if (i + K > n) {                    return -1;                }                for (int j = i; j < i + K; j++) {                    A[j] ^= 1;                }                ans++;            }        }        return ans;    }
    /**     * https://leetcode-cn.com/problems/minimum-number-of-k-consecutive-bit-flips/     * 时间复杂度O(n),空间复杂度O(n)     * @param A     * @param K     * @return     */    public int minKBitFlipsTwo(int[] A, int K) {        int ans = 0;        Deque<Integer> queue = new LinkedList<>();        for (int i = 0; i < A.length; i++) {            if (queue.size() > 0 && i > queue.peek() + K - 1) {                queue.removeFirst();            }            if (queue.size() % 2 == A[i]) {                if (i + K > A.length) {                    return -1;                }                queue.add(i);                ans++;            }        }        return ans;    }}