private void halfFruits(int nfruits) {
      int r;
      int subset[] = new int[6];
      boolean filled = false;

      for(int i=0; i < 6; i++) {
        boolean unique;
        do {
          unique = true;
          r = (int)(Math.random()*12);
          for(int j=0; j < i; j++) {
            if(subset[j] == r)
              unique = false;
          }
        }while(!unique);
        subset[i] = r;
      }

      while(nfruits > 0) {
        r = (int)(Math.random()*subset.length);
        dist[subset[r]]++ ;
        nfruits--;
      }
    }