![image](https://assets.leetcode.com/users/images/399baa8a-ec61-4dc7-b14f-8e33e7d98b60_1598312799.6803682.png)\n![image](https://assets.leetcode.com/users/images/ec917754-c253-4eea-8132-5bafdf5b612f_1598312799.8025446.png)\n![image](https://assets.leetcode.com/users/images/e6215bfc-4486-40ab-a76e-e0d6863ed796_1598312799.7496653.png)\n![image](https://assets.leetcode.com/users/images/8bc64275-0c20-44c5-9bbd-5719acd39fc7_1598312799.7651608.png)\n\nHow do I solve this with optimal complexity?

\n\n\n\n\nHow do I solve this with optimal complexity?