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?

题意：斐波那契数列

代码：

public class Solution {
    public int climbStairs(int n) {
        if(n == 1)
			return 1;
		if(n == 2)
			return 2;
        int[] methods = new int[n + 1];
        methods[1] = 1;
        methods[2] = 2;
        for(int i = 3; i <= n; i++)
        	methods[i] = methods[i - 1] + methods[i - 2];
        return methods[n];
    }
}