- push, pall
Implement the push and pall opcodes.
The push opcode
The opcode push pushes an element to the stack.
Usage: push where is an integer if 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 Format: see example If the stack is empty, don’t print anything
julien@ubuntu:~/monty$ cat -e bytecodes/00.m
push 1$
push 2$
push 3$
pall$
julien@ubuntu:~/monty$ ./monty bytecodes/00.m
3
2
1
julien@ubuntu:~/monty$
- pint
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
julien@ubuntu:~/monty$ cat bytecodes/06.m
push 1
pint
push 2
pint
push 3
pint
julien@ubuntu:~/monty$ ./monty bytecodes/06.m
1
2
3
julien@ubuntu:~/monty$
- pop
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
julien@ubuntu:~/monty$ cat bytecodes/07.m
push 1
push 2
push 3
pall
pop
pall
pop
pall
pop
pall
julien@ubuntu:~/monty$ ./monty bytecodes/07.m
3
2
1
2
1
1
julien@ubuntu:~/monty$
- swap
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
julien@ubuntu:~/monty$ cat bytecodes/09.m
push 1
push 2
push 3
pall
swap
pall
julien@ubuntu:~/monty$ ./monty bytecodes/09.m
3
2
1
2
3
1
julien@ubuntu:~/monty$
- add
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
julien@ubuntu:~/monty$ cat bytecodes/12.m
push 1
push 2
push 3
pall
add
pall
julien@ubuntu:~/monty$ ./monty bytecodes/12.m
3
2
1
5
1
julien@ubuntu:~/monty$
- nop
Implement the nop opcode.
The nop opcode
The opcode nop doesn’t do anything.
Usage: nop