백준 1309 동물원(Java)

https://www.acmicpc.net/problem/1309

1309번: 동물원

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Java 코드

 

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import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    
    int n = sc.nextInt();
    int[][] arr = new int[100001][3];
    arr[1][0] = 1;
    arr[1][1] = 1;
    arr[1][2] = 1;

    for(int i = 2; i <= n; i++) {
      arr[i][0] = (arr[i - 1][0] + arr[i - 1][1] + arr[i - 1][2]) % 9901;
      arr[i][1] = (arr[i - 1][0] + arr[i - 1][2]) % 9901;
      arr[i][2] = (arr[i - 1][0] + arr[i - 1][1]) % 9901;
    }
    
    int sum = (arr[n][0] + arr[n][1] + arr[n][2]) % 9901;
    
    System.out.println(sum);
  }
}