백준 11727

▶11727번 문제

 

▶풀이방법

 

import java.io.*;
public class Main{
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
		
		int num = Integer.parseInt(br.readLine());
		
		int[] dp = new int[num+2];
		dp[1] = 1;
		dp[2] = 3;
		
		for(int i = 3; i <= num; i++) {
			dp[i] = (dp[i-1] + 2*dp[i-2]) % 10007;
		}
		bw.write(String.valueOf(dp[num]));
		bw.flush();
		bw.close();
		br.close();
	}
}