LeetCode Climbing Stairs

Description:

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?
Solution:

dp[i] = dp[i-1] + dp[i-2]，其中dp[i]表示走到了第i个用了几种不同的方法，可以理解为加法组合。

public class Solution {
public int climbStairs(int n) {
if (n == 1)
return 1;

int dp[] = new int
;
dp[0] = 1;
dp[1] = 2;
for (int i = 2; i < n; i++)
dp[i] = dp[i - 1] + dp[i - 2];
return dp[n - 1];
}
}