# Stack & Queue
> ⚠️ **Experimental — generated with no human supervision.** This realm was
> produced automatically by an MCP-driven agent to exercise the gno MCP server
> and tooling, and to generate test content for gno compilers, linters and
> formatters. **Not audited. Not for production.** Full context & folder README:
> [r/moul/x/daily](https://github.com/moul/gno-contracts/blob/main/r/moul/x/daily/README.md)
---
An educational data-structure playground that maintains BOTH a LIFO **stack**
and a FIFO **queue** of ints side by side. Push/Pop the stack, Enqueue/Dequeue
the queue, and `Render` shows both structures with the top/front element
labeled, their sizes, and a one-line reminder of how LIFO differs from FIFO.
Popping or dequeuing an empty structure panics (a cross-realm abort).
Realm path: `gno.land/r/REPLACE_ADDR/stack`
## Example calls
```
# Stack (LIFO)
Push 1
Push 2
Push 3
Pop # -> 3
Pop # -> 2
# Queue (FIFO)
Enqueue 1
Enqueue 2
Enqueue 3
Dequeue # -> 1
Dequeue # -> 2
```
Via `gnokey`:
```sh
gnokey maketx call -pkgpath "gno.land/r/REPLACE_ADDR/stack" -func Push -args 42 ...
gnokey maketx call -pkgpath "gno.land/r/REPLACE_ADDR/stack" -func Pop ...
gnokey maketx call -pkgpath "gno.land/r/REPLACE_ADDR/stack" -func Enqueue -args 42 ...
gnokey maketx call -pkgpath "gno.land/r/REPLACE_ADDR/stack" -func Dequeue ...
```
Read the live view with `Render` (e.g. via `gnokey query vm/qrender`).
<!-- BEGIN GNOCONTRACTS FOOTER (generated by `make readmes`; do not edit below) -->
---
Part of **[moul/gno-contracts](https://github.com/moul/gno-contracts)** — moul's versioned gno.land contracts. See the repository for the full catalog, build/test tooling, and usage.
> 🧪 **Highly experimental — potentially vibe-coded.** Not audited; may break, change, or be removed at any time. Do not use with anything of value. Full disclaimer: [DISCLAIMER](https://github.com/moul/gno-contracts/blob/main/DISCLAIMER.md).
<!-- END GNOCONTRACTS FOOTER -->
Dequeue(cur interface {.seal func(); Address func() .uverse.address; IsCode func() bool; IsCurrent func() bool; IsEphemeral func() bool; IsUser func() bool; IsUserCall func() bool; IsUserRun func() bool; PkgPath func() string; Previous func() .uverse.realm; String func() string; Sub func(string) .uverse.realm; Subpath func() string}) int
Enqueue(cur interface {.seal func(); Address func() .uverse.address; IsCode func() bool; IsCurrent func() bool; IsEphemeral func() bool; IsUser func() bool; IsUserCall func() bool; IsUserRun func() bool; PkgPath func() string; Previous func() .uverse.realm; String func() string; Sub func(string) .uverse.realm; Subpath func() string}, n int)
Pop(cur interface {.seal func(); Address func() .uverse.address; IsCode func() bool; IsCurrent func() bool; IsEphemeral func() bool; IsUser func() bool; IsUserCall func() bool; IsUserRun func() bool; PkgPath func() string; Previous func() .uverse.realm; String func() string; Sub func(string) .uverse.realm; Subpath func() string}) int
Push(cur interface {.seal func(); Address func() .uverse.address; IsCode func() bool; IsCurrent func() bool; IsEphemeral func() bool; IsUser func() bool; IsUserCall func() bool; IsUserRun func() bool; PkgPath func() string; Previous func() .uverse.realm; String func() string; Sub func(string) .uverse.realm; Subpath func() string}, n int)
QueueSize() int
Render(path string) string
StackSize() int
Signatures reconstructed verbatim from vm/qfuncs — interface params keep their inline definitions.
vm/qrender output, sanitized (docs/render-security.md) and displayed in an empty-sandbox iframe — scripts, forms and popups cannot run. Links stay inert in-preview; right-click to open.