• 문제
  https://www.acmicpc.net/problem/11726 https://www.acmicpc.net/problem/11727
• 참고
  https://jaemin8852.tistory.com/157
  https://jaemin8852.tistory.com/158

설명

dp를 풀 때는 점화식을 구한다.

11726

11727

+) 숫자가 매우 커지니 dp[n] 을 구할 때, 10007로 나눈 나머지를 저장한다.

코드

11726

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
    static int n;
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        n = Integer.parseInt(br.readLine());

        int[] dp = new int[1001];

        dp[1] = 1;
        dp[2] = 2;

        for (int i = 3; i <= n; i++) {
            dp[i] = (dp[i - 1] + dp[i - 2]) % 10007;
        }

        System.out.print(dp[n]);
    }
}

11727

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
    static int n;
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        n = Integer.parseInt(br.readLine());

        int[] dp = new int[1001];

        dp[1] = 1;
        dp[2] = 3;

        for (int i = 3; i <= n; i++) {
            dp[i] = (dp[i - 1] + 2 * dp[i - 2]) % 10007;
        }
        System.out.println(dp[n]);
    }
}