0/1 > > > > > > > > > > > > > > > > > > 1/1 < < < < < < < < < < < < < < < < < < 1/0                 
                     |                                     * | *                                     |                  
                     |                                   *   |   *                                   |                  
                     |                                 *     |     *                                 |                  
                     |                               *       |       *                               |                  
                     |                             *         |         *                             |                  
                     |                           *           |           *                           |                  
                     |                         *             |             *                         |                  
                     |                       *               |               *                       |                  
                     |                     *                 |                 *                     |                  
                    0/1 > > > > > > > > 1/2 < < < < < < < < 1/1 > > > > > > > > 2/1 < < < < < < < < 1/0                 
                     |                   |                   |                   |                   |                  
                     |                   |                   |                   |                   |                  
                     |                   |                   |                   |                   |                  
                     |                   |                   |                   |                   |                  
                    0/1                 1/2                 1/1                 2/1                 1/0                 
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
 JFC                                                                                                                    
 www.lactamme.polytechnique.fr