Max Continuous Series of 1s

• Time : $O(n)$
• Space : $O(1)$

vector<int> Solution::maxone(vector<int> &A, int B) {
    int l = 0, r = 0, n = A.size(), now = 0;
    int len = 0, p = 0;
    while(r < n) {
        while(r < n and now <= B) {
            if(r - l > len) {
                len = r - l;
                p = l;
            }
            if(A[r++] == 0) now += 1;
        }
        if(now <= B and r - l > len) {
            len = r - l;
            p = l;
        }
        while(r < n and now > B) {
            if(A[l++] == 0) now -= 1;
        }
    }
    vector<int> res;
    for(int i = p; i < p + len; i++) res.push_back(i);
    return res;
}