1665 - Minimum Initial Energy to Finish Tasks\.

Hard

You are given an array tasks where <code>tasksi = actual_i, minimum_i</code>:

• <code>actual_i</code> is the actual amount of energy you spend to finish the <code>i^th</code> task.

• <code>minimum_i</code> is the minimum amount of energy you require to begin the <code>i^th</code> task.

For example, if the task is [10, 12] and your current energy is 11, you cannot start this task. However, if your current energy is 13, you can complete this task, and your energy will be 3 after finishing it.

You can finish the tasks in any order you like.

Return the minimum initial amount of energy you will need to finish all the tasks.

Example 1:

Input: tasks = \[\[1,2],2,4,4,8]

Output: 8

Explanation:

Starting with 8 energy, we finish the tasks in the following order:

- 3rd task. Now energy = 8 - 4 = 4.

- 2nd task. Now energy = 4 - 2 = 2.

- 1st task. Now energy = 2 - 1 = 1.

Notice that even though we have leftover energy, starting with 7 energy does not work because we cannot do the 3rd task.

Example 2:

Input: tasks = \[\[1,3],2,4,10,11,10,12,8,9]

Output: 32

Explanation:

Starting with 32 energy, we finish the tasks in the following order:

- 1st task. Now energy = 32 - 1 = 31.

- 2nd task. Now energy = 31 - 2 = 29.

- 3rd task. Now energy = 29 - 10 = 19.

- 4th task. Now energy = 19 - 10 = 9.

- 5th task. Now energy = 9 - 8 = 1.

Example 3:

Input: tasks = \[\[1,7],2,8,3,9,4,10,5,11,6,12]

Output: 27

Explanation:

Starting with 27 energy, we finish the tasks in the following order:

- 5th task. Now energy = 27 - 5 = 22.

- 2nd task. Now energy = 22 - 2 = 20.

- 3rd task. Now energy = 20 - 3 = 17.

- 1st task. Now energy = 17 - 1 = 16.

- 4th task. Now energy = 16 - 4 = 12.

- 6th task. Now energy = 12 - 6 = 6.

Constraints:

• <code>1 <= tasks.length <= 10⁵</code>

• <code>1 <= actual_i<= minimum_i<= 10⁴</code>