TADM2E 4.3

Algo -
If we create pair of (min1, max2n) (min1, max2n-1)... will provide optimal result
1) Sort the set of 2n element (n log n)
2) Now assign two pointers 
   Start: A[0]
   End:   A[2n-1]
   while (start < end)
      pair(start, end)
      start++
      end--
   EndLoop

--Max 06:55, 25 June 2010 (EDT)