--- 递归相关 --- #### [10- I. 斐波那契数列](https://leetcode-cn.com/problems/fei-bo-na-qi-shu-lie-lcof/) ```java class Solution { public int fib(int n) { if (n == 0 || n == 1) { return n; } int start = 0; int end = 1; int result = 0; for (int i = 2; i <= n; i++) { result = (start + end) % 1000000007; start = end; end = result; } return result; } } ```