Solution to The Monty Project 0 - Implement the push and pall opcodes
The push opcode
The opcode push pushes an element to the stack.
Usage: push <int>
where <int> is an integer
if <int> is not an integer or if there is no argument given to push, print the error message L<line_number>: usage: push integer, followed by a new line, and exit with the status EXIT_FAILURE
where is the line number in the file
You won’t have to deal with overflows. Use the atoi function
The pall opcode
The opcode pall prints all the values on the stack, starting from the top of the stack.
Usage pall
If the stack is empty, don’t print anything
1 - Implement the pint opcode
The pint opcode
The opcode pint prints the value at the top of the stack, followed by a new line.
Usage: pint
If the stack is empty, print the error message L<line_number>: can't pint, stack empty, followed by a new line, and exit with the status EXIT_FAILURE
2 - Implement the pop opcode
The pop opcode
The opcode pop removes the top element of the stack.
Usage: pop
If the stack is empty, print the error message L<line_number>: can't pop an empty stack, followed by a new line, and exit with the status EXIT_FAILURE
3 - Implement the swap opcode
The swap opcode
The opcode swap swaps the top two elements of the stack.
Usage: swap
If the stack contains less than two elements, print the error message L<line_number>: can't swap, stack too short, followed by a new line, and exit with the status EXIT_FAILURE
4 - Implement the add opcode
The add opcode
The opcode add adds the top two elements of the stack.
Usage: add
If the stack contains less than two elements, print the error message L<line_number>: can't add, stack too short, followed by a new line, and exit with the status EXIT_FAILURE
The result is stored in the second top element of the stack, and the top element is removed, so that at the end:
The top element of the stack contains the result
The stack is one element shorter
5 - Implement the nop opcode
Implement the nop opcode.
The nop opcode
The opcode nop doesn’t do anything.
Usage: nop
6 - Implement the sub opcode
Implement the sub opcode.
The sub opcode
The opcode sub subtracts the top element of the stack from the second top element of the stack.
Usage: sub
If the stack contains less than two elements, print the error message L<line_number>: can't sub, stack too short, followed by a new line, and exit with the status EXIT_FAILURE
The result is stored in the second top element of the stack, and the top element is removed, so that at the end:
The top element of the stack contains the result
The stack is one element shorter
7 - Implement the div opcode
Implement the div opcode.
The div opcode
The opcode div divides the second top element of the stack by the top element of the stack.
Usage: div
If the stack contains less than two elements, print the error message L<line_number>: can't div, stack too short, followed by a new line, and exit with the status EXIT_FAILURE
The result is stored in the second top element of the stack, and the top element is removed, so that at the end:
The top element of the stack contains the result
The stack is one element shorter
If the top element of the stack is 0, print the error message L<line_number>: division by zero, followed by a new line, and exit with the status EXIT_FAILURE
8 - Implement the mul opcode
Implement the mul opcode.
The mul opcode
The opcode mul multiplies the second top element of the stack with the top element of the stack.
Usage: mul
If the stack contains less than two elements, print the error message L<line_number>: can't mul, stack too short, followed by a new line, and exit with the status EXIT_FAILURE
The result is stored in the second top element of the stack, and the top element is removed, so that at the end:
The top element of the stack contains the result
The stack is one element shorter
9 - Implement the mod opcode
The mod opcode
The opcode mod computes the rest of the division of the second top element of the stack by the top element of the stack.
Usage: mod
If the stack contains less than two elements, print the error message L<line_number>: can't mod, stack too short, followed by a new line, and exit with the status EXIT_FAILURE
The result is stored in the second top element of the stack, and the top element is removed, so that at the end:
The top element of the stack contains the result
The stack is one element shorter
If the top element of the stack is 0, print the error message L<line_number>: division by zero, followed by a new line, and exit with the status EXIT_FAILURE
10 - Implement the commenting function
Every good language comes with the capability of commenting. When the first non-space character of a line is #, treat this line as a comment (don’t do anything).
11 - Implement the pchar opcode
The pchar opcode
The opcode pchar prints the char at the top of the stack, followed by a new line.
Usage: pchar
The integer stored at the top of the stack is treated as the ascii value of the character to be printed
If the value is not in the ascii table (man ascii) print the error message L<line_number>: can't pchar, value out of range, followed by a new line, and exit with the status EXIT_FAILURE
If the stack is empty, print the error message L<line_number>: can't pchar, stack empty, followed by a new line, and exit with the status EXIT_FAILURE
12 - Implement the pstr opcode
The pstr opcode
The opcode pstr prints the string starting at the top of the stack, followed by a new line.
Usage: pstr
The integer stored in each element of the stack is treated as the ascii value of the character to be printed
The string stops when either:
the stack is over
the value of the element is 0
the value of the element is not in the ascii table
If the stack is empty, print only a new line
13 - Implement the rotl opcode
The rotl opcode
The opcode rotl rotates the stack to the top.
Usage: rotl
The top element of the stack becomes the last one, and the second top element of the stack becomes the first one
rotl never fails
14 - Implement the rotr opcode
The rotr opcode
The opcode rotr rotates the stack to the bottom.
Usage: rotr
The last element of the stack becomes the top element of the stack
rotr never fails
15 - Implement the stack and queue opcodes
The stack opcode
The opcode stack sets the format of the data to a stack (LIFO). This is the default behavior of the program.
Usage: stack
The queue opcode
The opcode queue sets the format of the data to a queue (FIFO).
Usage: queue
When switching mode:
The top of the stack becomes the front of the queue
The front of the queue becomes the top of the stack
16 - Write a Brainfck script prints "School" followed by a new line
All your Brainf*ck files should be stored inside the bf sub directory
You can install the bf interpreter to test your code: sudo apt-get install bf
Read: Brainf*ck
17 - Adds two digits given by the user 18 - Multiply two digits given by the user 19 - Multiply two digits given by the user