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?

#include<iostream>
#include<vector>

using namespace std;

int climbStairs(int n) {

	vector<int>Setp(n+1,0);
	Setp[1] =1;
	Setp[2] =2;
	for (int i=3;i<Setp.size();++i)
		Setp[i] = Setp[i-1]+Setp[i-2];
	return  Setp[n];
}