hara

https://www.acmicpc.net/problem/2839 import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class a2839 { public static void main(String[] args) throws NumberFormatException, IOException { BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); int num=Integer.parseInt(br.readLine()); int[] a=new int[num+1]; a[0]=0; a[1]=-1; a[2]=-1; f..