You are climbing a stair case. It takes n steps to reach to the top.
Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?
//斐波那契数列的非递归解法以及递归解法
class Solution { public: int climbStairs(int n) { if(n == 1) return 1; if(n == 2) return 2; int pre = 1; int current = 1; for(int i = 2; i <= n; i++){ int tmp = current+pre; pre = current; current = tmp; } return current; } int climbStairsRecursive(int n){ if(n == 1) return 1; if(n == 2) return 2; return climbStairsRecursive(n-1)+climbStairsRecursive(n-2); } };
原文：http://www.cnblogs.com/xiuxiu55/p/6512697.html