+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++   
+                                                                                                                                                                                                                                                             +
+                                                         ----------------------                                                                                                                                                                             +
+                                                         ----------------------                                                                                                                                                                              +
+                                                         ----------------------                                                                                                                                                                              +
+                                                         ----------------------                                                 v1         &                                                                                                               +
+                                                         ----------------------                                           <1           __________                    T    _______                                                                  &      +
+                                                         ----------------------                                                                        ------    --------             -------                &            &                    v2    ________+
+                                                         ----------------------                                      <2                                                                         __  ____     _    _    _  _   __  ---   -  --                +
+                                                         ----------------------                                                                                                                                                                             +
+                                                         ----------------------                                <3                                                                                                                                            +
+                                                         ----------------------                                                                                                                                                                              +
+                                                         ----------------------               ____    -----                                                                                                                                                  +
+                                                          /\ \/\/\/\ \/\/ /\/           &                                                                                                                                                                    +
+                                                   -  -  ----__----__----__----__     ____                                                                                                                                                                   +
+                                               -   -  -                                                                                                                                                                                                      +
+     v1    v2    \ \ \ & \ \ \\            -   -   -  -                                                                                                                                                                                                      +
+              __________________----   --  -   -   -  -                                                                                                                                                                                                      +
+                                                                                                                                                                                                                                                             +
+                                                                                                                                                                                                                                                             +
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++   
