LeetCode 70. Climbing Stairs

原题：

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?

Note: Given n will be a positive integer

Example 1:

Input: 2
Output: 2
Explanation: There are two ways to climb to the top.

1. 1 step + 1 step
2. 2 stepsExample
2:

Input: 3
Output:  3
Explanation:  There are three ways to climb to the top.

1. 1 step + 1 step + 1 step
2. 1 step + 2 steps
3. 2 steps + 1 step

题意：62,63的一维数组版，也是走台阶

思路及代码：

//二维数组走台阶的简化版
class Solution {
public int climbStairs(int n) {
if(n==0||n==1||n==2) return n;
int [] temp = new int
;
//第一层台阶一种走法（只能走一
4000
步）
temp[0] = 1;
//第二层台阶两种走法（1+1 or 2）
temp[1] = 2;
for(int i = 2;i<n;i++){
//第i层台阶的走法是前两层走法之和
temp[i] = temp[i-1] + temp[i-2];
}
return temp[n-1];
}
}