Day 03: LeetCode 1137 [Tribonacci Number]
doing on more problem with similar approach Problem Description: The Tribonacci sequence Tn is defined as follows:
T0 = 0, T1 = 1, T2 = 1, and Tn+3 = Tn + Tn+1 + Tn+2 for n >= 0.
Given n, return the value of Tn.
Example 1: Input: n = 4 Output: 4 Explanation: T_3 = 0 + 1 + 1 = 2 T_4 = 1 + 1 + 2 = 4 Example 2: Input: n = 25 Output: 1389537
Constraints: 0 <= n <= 37 The answer is guaranteed to fit within a 32-bit integer, ie. answer <= 2^31 - 1.
Link to LeetCode Problem: https://leetcode.com/problems/n-th-tribonacci-number/description/
My Thought Process:
- Tribonacci series : 0 1 1 2 4 7 13 ....
- for 0 & 1 returning 0 & 1 resp
- for 2 returning n2 i.e. is 1
- for fourth term adding 0+1+1=2 (which is n4) and returning
- then 1+1+2 which is 4 and so on
