[BOJ]2579_계단 오르기

문제_2589

코드 >>

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class boj_2579 {

	static int n, check = 0;
	static int[] score;
	static int[][] dp;

	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		n = Integer.parseInt(br.readLine());
		dp = new int[n][3];
		score = new int[n];

		for (int i = 0; i < n; i++)
			score[i] = Integer.parseInt(br.readLine());

		dp[0][0] = dp[0][1] = dp[0][2] = score[0];
		dp[1][0] = score[0]; 
		dp[1][1] = score[1]; 
		dp[1][2] = dp[0][1] + score[1]; 

		for (int i = 2; i < n; ++i) {
			dp[i][0] = Math.max(dp[i - 1][1], dp[i - 1][2]);
			dp[i][1] = dp[i - 1][0] + score[i];
			dp[i][2] = dp[i - 1][1] + score[i];
		}
		System.out.println(dp[n - 1][1] < dp[n - 1][2] ? dp[n - 1][2] : dp[n - 1][1]);
	}

}

해설 >>