import java.io.* ;
public class cakes {
   public static void main(String[] args) throws Exception {
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in)) ;
      while (true) {
         String[] f = br.readLine().split(" ") ;
         if (f.length < 2)
            break ;
         boolean b[][] = new boolean[500][500] ;
         b[0][0] = true ;
         int sum = 0 ;
         for (int i=1; i<f.length; i++) {
            int ct = Integer.parseInt(f[i]) ;
            sum += ct ;
            for (int j=499; j>=0; j--)
               for (int k=499; k>=0; k--)
                  b[j][k] |= (j >= ct && b[j-ct][k]) | (k >= ct && b[j][k-ct]) ;
         }
         int r = 500 ;
         for (int i=0; i<r; i++)
            for (int j=0; j<r; j++)
               if (b[i][j] && sum-i-j < r)
                  r = Math.max(Math.min(i, j), sum-i-j) ;
         System.out.println(r) ;
      }
   }
}