\"\"

\

The expression is \"\"

\

\"\"                                         (Substitute \"\")

\

\"\"                                                 (Multiply: \"\")

\

\"\"                                                        (Add: \"\")\"\"

\

\"\"                                                             (Subtract: \"\")

\

\"\"                                                                        (Add: \"\")\"\"

\

The  value of expression is  \"\".