题解 | #吃糖果#

#include<iostream>
#include<string>
#include<vector>
#include<algorithm>

using namespace std;


int N;
int count_num = 0;
void DFS(int day, int sum) {
    if (sum == N) {
        count_num++;
    } else {
        if (sum + 1 <= N) {
            DFS(day + 1, sum + 1);
        }
        if (sum + 2 <= N) {
            DFS(day + 1, sum + 2);
        }
    }
}


int main() {

    scanf("%d", &N);
    DFS(1, 0);
    cout << count_num;
}