Hi all,

Had an interview recently for an SDE role in visa

DSA Round

The interviewer gave me a problem on:

Tree traversal + state tracking (with constraints on child nodes)

At first, it looked manageable.

I started with:

• Basic DFS approach
• Tried to track values while traversing

But then the follow up question and twist came:

• Needed to carry state across levels
• And avoid recomputation

I knew this was heading toward DP but I couldn’t structure it cleanly

So midway:

• My solution became messy
• Edge cases started breaking
• I had to backtrack

That killed my momentum.

Next Round (LLD)

Got a design problem around:

Booking / ordering type system

Focused on:

• Clean class structure
• Separation of concerns
• Handling different scenarios

This round felt much better more like a discussion than an interview.

Final Result

Selected

Honestly, I didn’t expect this after the DSA round.