4 Questions\n\n![image](https://assets.leetcode.com/users/images/cb6badf8-fbca-476a-b8f8-342b8312fa9f_1599488770.9104345.png)\n\n\n![image](https://assets.leetcode.com/users/images/a150c7c2-172b-455d-9837-6aa44d71dc02_1599488779.2167704.png)\n\n![image](https://assets.leetcode.com/users/images/ae2b628c-1255-412a-9aab-7307585090b5_1599488797.3420196.png)\n\n![image](https://assets.leetcode.com/users/images/1a10bbaa-a962-46ad-b466-d731dccfb4ee_1599488808.973848.png)\n\n\t