//左邊界
public static int bSearch1(int l, int r){
? ?while (l < r){
? ? ? ?int mid = l + r >> 1;
? ? ? ?if (check(mid)) r = mid;
? ? ? ?else l= mid + 1;
? ?}
? ?return l;
}

//右邊界
public static int bSearch2(int l, int r){
? ?while (l < r){
? ? ? ?int mid = l + r ?+ 1 >> 1;
? ? ? ?if (check(mid)) l = mid;
? ? ? ?else r = mid - 1;
? ?}
? ?return l;
}