题源:leetcode
链接:https://leetcode-cn.com/problems/fibonacci-number/
最基础的动态规划:
1 class Solution { 2 public: 3 int fib(int n) { 4 if (n < 2) { 5 return n; 6 } 7 int p = 0, q = 0, r = 1; 8 for (int i = 2; i <= n; ++i) { 9 p = q; 10 q = r; 11 r = p + q; 12 } 13 return r; 14 } 15 };