using System;
namespace acm1005
{
    class Program
    {
        public static int[] w=new int[21];
        public static bool[] f;
        public static int DP_StonePile(int n)
        {
            int total=0;
            for(int i=1;i<=n;i++) total+=w[i];
            int avg=total/2;
            f=new bool[total];
            f[0]=true;
            int max=0;
            for(int j=1;j<=n;j++)
                for(int i=avg-w[j];i>=0;i--)
                {
                    if(f[i]==true)
                    {
                        f[i+w[j]]=true;
                        if(i+w[j]>max) max=i+w[j];
                    }
                }
            return total-2*max;
        }
        public static void Main(string[] args)
        {
            int n=Int32.Parse(Console.ReadLine());
            for(int i=1;i<=n;i++)
                w[i]=Int32.Parse(Console.ReadLine());
            Console.WriteLine(DP_StonePile(n));
            //Console.Write("Press any key to continue . . . ");
            //Console.ReadKey(true);
        }
    }
}

Mine too @.@

OH I got Crash on test #4 ,too`~~~