WeRide·Software Engineer·Technical Phone Screen
Jun 2026
WeRide software engineer interview focused entirely on math-heavy algorithm problems: matrix multiplication, fast exponentiation, and Fibonacci via matrix exponentiation. Pretty niche stuff, felt more like a competitive programming screen than a typical SWE interview.
- Implement matrix multiplication for an n×m matrix A and an m×p matrix B, returning the resulting n×p matrix C. Handle modular arithmetic if a MOD value is provided.
- Implement fast exponentiation: given x, k, and an optional MOD, compute x^k (mod MOD) in O(log k) time. Handle edge cases like k=0 and x=0.
- Compute the nth Fibonacci number (n >= 0) using matrix exponentiation to achieve O(log n) time complexity. Apply modular arithmetic where required.
“Pretty straightforward once you get the dimensions right, but I fumbled the index order on my first pass and had to back up.” The rest of the author's notes on Software Engineer interview at WeRide, Technical Phone Screen round, covers how they worked through the question, what the panel pushed back on, and what they would do differently.
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