{{{ import java.util.Scanner; public class JollyJumpers{ public static void main(String [] args) { Scanner scan = new Scanner(System.in); int[] arr = new int[3000]; while(scan.hasNextInt()){ int size = scan.nextInt(); int i; for(i=0; i= size)//size 넘어가면 1~n-1을 넘어가니까. return false; else jollyNum[Math.abs(arr[i+1]-arr[i])]++; } for(int i=1; i<=size-1;i++){ if(jollyNum[i] == 0)//1~n-1 중 하나라도 포함 안하면 not jolly return false; } return true; } } }}} ---- [ACM_ICPC/2011년스터디]