[백준] 2579번 : 계단 오르기 - Kotlin(코틀린)

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

import java.util.*;
fun main() {
    val s:Scanner=Scanner(System.`in`)
    var n=s.nextInt()
    var arr=Array<Int>(n+1) {0}
    var num=Array<Int>(n+1) {0}
    for(i in 1..n){
        arr[i]=s.nextInt()
    }
    num[1]=arr[1]
    if(n>1) num[2]=arr[1]+arr[2]
    for(i in 3..n){
        num[i]=Math.max(num[i-2],num[i-3]+arr[i-1])+arr[i]
    }
    print(num[n])
}