[leetcode]Climbing Stairs

新博文地址：[leetcode]Climbing Stairs

http://oj.leetcode.com/problems/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?

 是不是很熟悉？跟青蛙上台阶一样一样滴。。。菲波那切数列，不罗嗦

两种方法：

1. 递归（大量冗余计算，可能超时）

2. 循环

   public int climbStairs(int n) {
		if (n == 0 || n == 1) {
			return 1;
		}
		int[] array = new int[n + 1];
		array[1] = 1;
		array[2] = 2;
		
		for (int i = 3; i <= n; i++) {
			array[i] = array[i-1] + array[i-2];
		}
		return array[n];
		}