题解 | #N阶楼梯上楼问题#

#include <bits/stdc++.h>
#define MAX 100
using namespace std;

int main(){
	int dp[MAX],n;
	while(cin>>n){
		dp[0] = 0;
		dp[1] = 1;
		dp[2] = 2;
		for(int i = 3; i <= n; i++)
			dp[i] = dp[i-1] + dp[i-2];
		cout<<dp[n];	
	}

}