Stack: Difference between revisions

</pre>

=={{header|Action!}}==

===Static memory===

<lang Action!>DEFINE MAXSIZE="200"

BYTE ARRAY stack(MAXSIZE)

BYTE stacksize=[0]

BYTE FUNC IsEmpty()

IF stacksize=0 THEN

RETURN (1)

FI

RETURN (0)

PROC Push(BYTE v)

IF stacksize=maxsize THEN

PrintE("Error: stack is full!")

Break()

FI

stack(stacksize)=v

stacksize==+1

RETURN

BYTE FUNC Pop()

IF IsEmpty() THEN

PrintE("Error: stack is empty!")

Break()

FI

stacksize==-1

RETURN (stack(stacksize))

PROC TestIsEmpty()

IF IsEmpty() THEN

PrintE("Stack is empty")

ELSE

PrintE("Stack is not empty")

FI

RETURN

PROC TestPush(BYTE v)

PrintF("Push: %B%E",v)

Push(v)

RETURN

PROC TestPop()

BYTE v

Print("Pop: ")

v=Pop()

PrintBE(v)

RETURN

PROC Main()

TestIsEmpty()

TestPush(10)

TestIsEmpty()

TestPush(31)

TestPop()

TestIsEmpty()

TestPush(5)

TestPop()

TestPop()

TestPop()

RETURN</lang>

===Dynamic memory===

The user must type in the monitor the following command after compilation and before running the program!<pre>SET EndProg=*</pre>

{{libheader|Action! Tool Kit}}

<lang Action!>CARD EndProg ;required for ALLOCATE.ACT

INCLUDE "D2:ALLOCATE.ACT" ;from the Action! Tool Kit. You must type 'SET EndProg=*' from the monitor after compiling, but before running this program!

DEFINE PTR="CARD"

DEFINE NODE_SIZE="3"

TYPE StackNode=[BYTE data PTR nxt]

StackNode POINTER stack

BYTE FUNC IsEmpty()

IF stack=0 THEN

RETURN (1)

FI

RETURN (0)

PROC Push(BYTE v)

StackNode POINTER node

node=Alloc(NODE_SIZE)

node.data=v

node.nxt=stack

stack=node

RETURN

BYTE FUNC Pop()

StackNode POINTER node

BYTE v

IF IsEmpty() THEN

PrintE("Error stack is empty!")

Break()

FI

node=stack

v=node.data

stack=node.nxt

Free(node,NODE_SIZE)

RETURN (v)

PROC TestIsEmpty()

IF IsEmpty() THEN

PrintE("Stack is empty")

ELSE

PrintE("Stack is not empty")

FI

RETURN

PROC TestPush(BYTE v)

PrintF("Push: %B%E",v)

Push(v)

RETURN

PROC TestPop()

BYTE v

Print("Pop: ")

v=Pop()

PrintBE(v)

RETURN

PROC Main()

AllocInit(0)

stack=0

Put(125) PutE() ;clear screen

TestIsEmpty()

TestPush(10)

TestIsEmpty()

TestPush(31)

TestPop()

TestIsEmpty()

TestPush(5)

TestPop()

TestPop()

TestPop()

RETURN</lang>

{{out}}

Error at the end of program is intentional.

[https://gitlab.com/amarok8bit/action-rosetta-code/-/raw/master/images/Stack_array.png Screenshot from Atari 8-bit computer]

<pre>

Stack is empty

Push: 10

Stack is not empty

Push: 31

Pop: 31

Stack is not empty

Push: 5

Pop: 5

Pop: 10

Pop: Error: stack is empty!

RETURN

Error: 128