LeetCode-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?

class Solution {
public:
    int climbStairs(int n) {
        // Note: The Solution object is instantiated only once and is reused by each test case.
        vector<int> ways;
        ways.resize(n+1,0);
        ways[0]=1;
        ways[1]=1;
        for(int i=2;i<=n;i++){
            ways[i]=ways[i-1]+ways[i-2];
        }
        return ways[n];
    }
};