leetcode--Climbing Stairs

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?

[java]  view plain  copy

1. public class Solution {  
2.     public int climbStairs(int n) {  
3.         if(n==1) return 1;  
4.         int[] res = new int[2];  
5.         res[0] = 1;  
6.         res[1] = 2;  
7.         while(n>2){        
8.             int t = res[1];  
9.             res[1] += res[0];  
10.             res[0] = t;  
11.             n--;  
12.         }  
13.         return res[1];  
14.     }  
15. } 

原文链接http://blog.youkuaiyun.com/crazy__chen/article/details/46376009