LeetCode - 70. Climbing Stairs(0ms)

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 steps

Example 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

 1 class Solution {
 2 public:
 3     int climbStairs(int n) {
 4         if(n == 1)
 5             return 1;
 6         
 7         int res[n + 1];
 8         res[0] = 1;
 9         res[1] = 1;
10         for(int i = 2; i <= n; i++)
11             res[i] = res[i - 1] + res[i - 2];
12         return res[n];
13     }
14 };