4.24 京东笔试
选择题的shell，Linux，一脸懵逼，菜狗不会shell，Linux
算法题就挺水的。。。
第二题比较奇淫
import java.util.*;
public class Main{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int n = sc.nextInt();
sc.nextLine();
// get data
int N = 998244353;
int[] dp = new int[n+1];
dp[0] = 0;
dp[1] = 1;
dp[2] = 1;
dp[3] = 2;
for (int i = 4; i <= n; i++){
dp[i] = (dp[i-1] + dp[i-3]) % N;
}
System.out.println(dp[n]);
}
} 
