You have `n` flower seeds. Every seed must be planted first before it can begin to grow, then bloom. Planting a seed takes time and so does the growth of a seed. You are given two 0-indexed integer arrays `plantTime` and `growTime`, of length `n` each:

- `plantTime[i]` is the number of full days it takes you to plant the `ith` seed. Every day, you can work on planting exactly one seed. You do not have to work on planting the same seed on consecutive days, but the planting of a seed is not complete until you have worked `plantTime[i]` days on planting it in total.
- `growTime[i]` is the number of full days it takes the `ith` seed to grow after being completely planted. After the last day of its growth, the flower blooms and stays bloomed forever.

From the beginning of day `0`, you can plant the seeds in any order.

Return the earliest possible day where all seeds are blooming.

Example 1:

    Input: plantTime = [1,4,3], growTime = [2,3,1]
    Output: 9
    Explanation: The grayed out pots represent planting days, colored pots represent growing days, and the flower represents the day it blooms.
    One optimal way is:
    On day 0, plant the 0th seed. The seed grows for 2 full days and blooms on day 3.
    On days 1, 2, 3, and 4, plant the 1st seed. The seed grows for 3 full days and blooms on day 8.
    On days 5, 6, and 7, plant the 2nd seed. The seed grows for 1 full day and blooms on day 9.
    Thus, on day 9, all the seeds are blooming.

Example 2:

    Input: plantTime = [1,2,3,2], growTime = [2,1,2,1]
    Output: 9
    Explanation: The grayed out pots represent planting days, colored pots represent growing days, and the flower represents the day it blooms.
    One optimal way is:
    On day 1, plant the 0th seed. The seed grows for 2 full days and blooms on day 4.
    On days 0 and 3, plant the 1st seed. The seed grows for 1 full day and blooms on day 5.
    On days 2, 4, and 5, plant the 2nd seed. The seed grows for 2 full days and blooms on day 8.
    On days 6 and 7, plant the 3rd seed. The seed grows for 1 full day and blooms on day 9.
    Thus, on day 9, all the seeds are blooming.

Example 3:

    Input: plantTime = [1], growTime = [1]
    Output: 2
    Explanation: On day 0, plant the 0th seed. The seed grows for 1 full day and blooms on day 2.
    Thus, on day 2, all the seeds are blooming.

Constraints:

- `n == plantTime.length == growTime.length`
- `1 <= n <= 105`
- `1 <= plantTime[i], growTime[i] <= 104`