题解 | #吃糖果#

#include<iostream>
using namespace std;

const int N = 20;

int arr[N];

int main(void)
{
	int n;
	cin >> n;
	arr[0] = 1;
	arr[1] = 2;
	for(int i = 2;i < n;i++) arr[i] = arr[i - 1] + arr[i - 2];
	cout << arr[n - 1] << endl;
	return 0;
}