bash-4.2$ pwd
/home/cscccl/public_html/csc123
bash-4.2$ which mcs 
/usr/bin/mcs
bash-4.2$ mcs exptree3c.cs
exptree3c.cs(70): error CS1929: Type `expr' does not contain a member `size' and the best extension method overload `extend.size(this intnode)' requires an instance of type `intnode'
exptree3c.cs(76): (Location of the symbol related to previous error)
exptree3c.cs(78): error CS0122: `operatornode.left' is inaccessible due to its protection level
exptree3c.cs(78): error CS1540: Cannot access protected member `operatornode.left' via a qualifier of type `plusnode'. The qualifier must be of type `extend' or derived from it
exptree3c.cs(34): (Location of the symbol related to previous error)
exptree3c.cs(78): error CS1929: Type `expr' does not contain a member `size' and the best extension method overload `extend.size(this intnode)' requires an instance of type `intnode'
exptree3c.cs(76): (Location of the symbol related to previous error)
exptree3c.cs(80): error CS0122: `operatornode.left' is inaccessible due to its protection level
exptree3c.cs(80): error CS1540: Cannot access protected member `operatornode.left' via a qualifier of type `timesnode'. The qualifier must be of type `extend' or derived from it
exptree3c.cs(34): (Location of the symbol related to previous error)
exptree3c.cs(80): error CS1929: Type `expr' does not contain a member `size' and the best extension method overload `extend.size(this intnode)' requires an instance of type `intnode'
exptree3c.cs(76): (Location of the symbol related to previous error)
exptree3c.cs(82): error CS0122: `uminusnode.left' is inaccessible due to its protection level
exptree3c.cs(82): error CS1929: Type `expr' does not contain a member `size' and the best extension method overload `extend.size(this intnode)' requires an instance of type `intnode'
exptree3c.cs(76): (Location of the symbol related to previous error)
Compilation failed: 9 error(s), 0 warnings
bash-4.2$ exptree3c.cs(80): error CS0122: `operatornode.left' is inaccessible due to its protection level
bash: syntax error near unexpected token `80'
bash-4.2$ mcs exptree3c.cs
exptree3c.cs(81): error CS0122: `operatornode.left' is inaccessible due to its protection level
exptree3c.cs(81): error CS1540: Cannot access protected member `operatornode.left' via a qualifier of type `plusnode'. The qualifier must be of type `extend' or derived from it
exptree3c.cs(34): (Location of the symbol related to previous error)
exptree3c.cs(81): error CS0122: `operatornode.right' is inaccessible due to its protection level
exptree3c.cs(81): error CS1540: Cannot access protected member `operatornode.right' via a qualifier of type `plusnode'. The qualifier must be of type `extend' or derived from it
exptree3c.cs(34): (Location of the symbol related to previous error)
exptree3c.cs(83): error CS0122: `operatornode.left' is inaccessible due to its protection level
exptree3c.cs(83): error CS1540: Cannot access protected member `operatornode.left' via a qualifier of type `timesnode'. The qualifier must be of type `extend' or derived from it
exptree3c.cs(34): (Location of the symbol related to previous error)
exptree3c.cs(83): error CS0122: `operatornode.right' is inaccessible due to its protection level
exptree3c.cs(83): error CS1540: Cannot access protected member `operatornode.right' via a qualifier of type `timesnode'. The qualifier must be of type `extend' or derived from it
exptree3c.cs(34): (Location of the symbol related to previous error)
exptree3c.cs(85): error CS0122: `uminusnode.left' is inaccessible due to its protection level
Compilation failed: 9 error(s), 0 warnings
bash-4.2$ exptree3c.cs(81): error CS1540: Cannot access protected member `operatornode.right' via a qualifier of type `plusnode'. The qualifier must be of type `extend' or derived from it
bash: syntax error near unexpected token `81'
bash-4.2$ mcs exptree3c.cs
exptree3c.cs(85): error CS0122: `uminusnode.left' is inaccessible due to its protection level
Compilation failed: 1 error(s), 0 warnings
bash-4.2$ mcs exptree3b.cs
bash-4.2$ mono exptree3b.exe
(+ (* 2 3) (+ 1 4))
value is 11
size is 1
bash-4.2$ mcs exptree3b.cs
bash-4.2$ mono exptree3b.exe
(+ (* 2 3) (+ 1 4))
value is 11
size is 1
bash-4.2$