题解 | #吃糖果#

#include<cstdio>
using namespace std;

const int MAXN = 20;
int eat(int n) {
    int dp[3];
    dp[1] = 1;
    dp[2] = 2;
    int sum = 0;
    for (int i = 3; i <= n; ++i) {
        sum = dp[1] + dp[2];
        dp[1] = dp[2];
        dp[2] = sum;
    }
    return dp[2];
}
int main() {
    int n;
    while(scanf("%d", &n) != EOF) {
        if(n <= 2) {
            printf("%d\n", n);
        } else {
            int m = eat(n);
            printf("%d\n", m);
        }
    }
}