[Leetcode][python] 1137. N-th Tribonacci Number - DP

Problem

• Leetcode 1137. N-th Tribonacci Number - DP
• Level: Easy
• Link

N-th Tribonacci Number - LeetCode

 

My Approach

Classic fibonacci problem with DP algorithm

class Solution:
    def tribonacci(self, n: int) -> int:
        arr = [0, 1, 1]
        if n < 3:
            return arr[n]
        
        for i in range(3, n + 1):
            nxt = arr[i - 1] + arr[i - 2] + arr[i - 3]
            arr.append(nxt)
        
        return arr[n]