/**
 * Collecting money via divide-and-conquer method.
 * 
 * @author (Stefan Edelkamp) 
 * @version (2013)
 */
public class CollectMoney
{
    int total;
    /**
     * Divide and conquer method to collect money from friends
     * 
     * @param  a   amount to be distributed, preferably n=2^k
     * @return     approximately the same amount a 
     */
    void dac(int a) {  // recursive collect function
      if (a<=1) // if less than one Euro left
      total += a; // increase total amount 
      else { dac(a/2); dac(a/2);} // recursive calls
    }
    int collect(int a) {
      total = 0;
      dac(a);
      return total;
    }
}