Delete and Earn

arrayhash tabledynamic programming

Problem Statement

You are given an integer array nums . You want to maximize the number of points you get by performing the following operation any number of times:

Pick any nums[i] and delete it to earn nums[i] points. Afterwards, you must delete every element equal to nums[i] - 1 and every element equal to nums[i] + 1 .

Return the maximum number of points you can earn by applying the above operation some number of times .

Examples

Example 1

Input: nums = [3,4,2]
Output: 6
You can perform the following operations:
- Delete 4 to earn 4 points. Consequently, 3 is also deleted. nums = [2].
- Delete 2 to earn 2 points. nums = [].
You earn a total of 6 points.

Example 2

Input: nums = [2,2,3,3,3,4]
Output: 9
You can perform the following operations:
- Delete a 3 to earn 3 points. All 2's and 4's are also deleted. nums = [3,3].
- Delete a 3 again to earn 3 points. nums = [3].
- Delete a 3 once more to earn 3 points. nums = [].
You earn a total of 9 points.

Constraints

1 <= nums.length <= 2 * 10 ^4

1 <= nums[i] <= 10 ^4

🤔

Medium

Difficulty

Topic Info

ModuleDSA

CategoryArray

Sub-topicHash Table