673. Number of Longest Increasing Subsequence

https://leetcode.com/problems/number-of-longest-increasing-subsequence/

Python

class Solution:
    def findNumberOfLIS(self, nums: List[int]) -> int:
        n = len(nums)
        dp = [1 for _ in range(n)]
        counter = [1 for _ in range(n)]

        max_item = 1

        for i in range(1, n):
            for j in range(i):
                if nums[i] <= nums[j]:
                    continue

                if dp[i] == dp[j]+1:
                    counter[i] += counter[j]
                    continue

                if dp[i] < dp[j]+1:
                    dp[i] = dp[j] + 1
                    counter[i] = counter[j]
            max_item = max(max_item, dp[i])

        ans = 0
        for i, item in enumerate(dp):
            if item == max_item:
                ans += counter[i]
        return ans