740. Delete And Earn

Medium

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.

Example 1:

Input: nums = [3,4,2]
Output: 6
Explanation: 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
Explanation: 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 * 10⁴
1 <= nums[i] <= 10⁴

 class Solution:
    def deleteAndEarn(self, nums: List[int]) -> int:
        count = Counter(nums)
        num = sorted(set(nums))


        num1 = 0
        num2 = 0

        for i, n in enumerate(num):
            currentEarn = n*count[n]

            if n > 0 and n == num[i-1]+1:
                temp = max(num2, num1+currentEarn)
                num1 = num2
                num2 = temp

            else:
                temp = num2+currentEarn
                num1 = num2
                num2 = temp

        return num2

Random note