9. Convert the following expressions from reverse Polish notation to infix notation.
a) W X Y Z+-
b) U V W X Y Z + + +
c) X Y Z + V W- Z + +
a) WXYZ+-*
=> WX(Y+Z)-*
=> W(X-(Y+Z))*
=> (W*(X-(Y+Z))
b) UVWXYZ+*+*+
=> UVWX(Y+Z)*+*+
=> UVW(X*(Y+Z))+*+
=> UV(W+(X*(Y+Z)))*+
=> (U+(V*(W+(X*(Y+Z)))))
c) XYZ+VW-*Z++
=> X(Y+Z)(V-W)*Z++
=> X((Y+Z)*(V-W))Z++
=> X(((Y+Z)*(V-W))+Z)+
=> (X+(((Y+Z)*(V-W))+Z))