leetcode-progress-cpp/70-Climbing-Stairs.cpp at main · erictaur/leetcode-progress-cpp · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
class Solution {
public:
    int climbStairs(int n) {
        int ans = 0;
        vector<int> dp(n+1, 1);

        if(n >2){
            dp[1] = 1;
            dp[2] = 2;
        }
        else if(n == 1){
            return 1;
        }
        else{
            return 2;
        }


        for(int i=3; i<=n; i++){
            dp[i] = dp[i-1] + dp[i-2];
        }

        return dp[n];
    }
};

/* 70. Climbing-Stairs.cpp
//////////////////////////////////////////////////
You are climbing a staircase. It takes n steps to reach the top.

Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?

Input: n = 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

https://leetcode.com/problems/climbing-stairs/
//////////////////////////////////////////////////
*/