BEAKJOON JAVA ALGORITHM #2579(계단 오르기)

https://www.acmicpc.net/problem/2579

import java.util.Scanner; public class a2579 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int num = sc.nextInt(); int[] arr = new int[num+1]; for(int i=1; i<=num; i++) { arr[i] = sc.nextInt(); } //이중배열 /*int[][] d = new int[num+1][3]; d[1][1] = arr[1]; for(int i=2; i<=num; i++) { d[i][1] = Math.max(d[i-2][1], d[i-2][2]) + arr[i]; d[i][2] = d[i-1][1] + arr[i]; } System.out.println(Math.max(d[num][1], d[num][2]));*/ int[] d = new int[num+1]; d[1] = arr[1]; d[2] = arr[1] + arr[2]; for(int i=3; i<=num; i++) { d[i] = Math.max(d[i-2]+arr[i], d[i-3]+arr[i]+arr[i-1]); } System.out.println(d[num]); } }