Welcome to 2025-IonQ Discussions!

[Vadikus]

👋 Welcome!

We’re using Discussions as a place to connect with other members of our community. We hope that you:

• Explain your approach toward the challenge.
• Share ideas.
• Engage with other community members.
• Welcome others and are open-minded. Remember that this is a community we
  build together 💪.

To get started, comment below with an introduction of yourself and tell us about what you thinkin abou the IonQ iQuHack2025 challenge.

[zealair12]

I'm Zeal. I chose the red pill and had to go back for the blue pill.... don't go for the red pill guys. I think the mosh-pit and employee analogy helped me understand the problem beyond just another graph problem. I'm yet to get started though.

[FarzanaR11]

This gotta be the most humorous yet crazy brainstorming challenge I've ever solved I must say lol 😂

[limitless-100]

I am Samuel from Nigeria, and part of "unlimitedCut" team. Kudos to the problem setters! 👍 You all did a fantastic job! 🤣 🤣 Enjoy our short poem:

THE MOSH-PIT COMPUTING
For several days, I prepared for this contest,
At the end, I was given "more-shit computing,"
Turned me into a code-sweating monkey under an air conditioner.

To Challenge 1, I said, "Wow, IonQ went easy this year,"
While Challenge 3 patiently waited for my foolish self.
"Quantum stuff runs at light speed," they say,
Yet my quantum ansatz is still running since Big Bang Era.

Balanced max-cut says 358 out of 100,000.
"Indeed, well balanced!" I burst into laughter.
Connected max-cut says 0 out of 100,000.
Yet, "All subgraphs must be connected," say the instructions.
Clearly, IonQ staff were never connected in real life.
Time to withdraw my internship applications from them.

Brain is not braining anymore,
Mind is on airplane mode,
I have aged 50 years faster since I have started this contest,
My head is just a decorative piece of art today.

Annual Intellectual torture,
Overwhelming stress,
Nearly lost my sanity,
Quit.
I O N Q!!!

[peiyanli23]

I think the most important thing is to set connection between the process both constructing circuits and solving for the maxcut.

[mulliganaceous]

An idea for the MST might work. The problem is that edges must be sequentially numbered and it still involves something of the form $e_{ku}$ which states "edge $k$" contains $u$ as endpoint.

[mulliganaceous]

My final attempt involved an insane ansatz, and three QUBO constraints... All in terms of edges...

No disconnections

This term is linear in $e_{vw}$.
$\sum_{(v, w) \notin E} e_{vw} = 0$

No intergroup pairings

This term is cubic in the $e$ and $x$. Let's see if this is compatible with our QUBO solver...
$ \sum_{v = 0}^{N - 1} \sum_{w = 0}^{N - 1} (1 - x - y + 2xy) e_{vw} = 0$

All vertices must be used

These $N$ terms are linear in $e_{vw}$.
$ \forall v \sum_{w = v + 1}^{N - 1} e_{vw} \geq 1 $