Your question is Where to Place Chargers in a New City. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
How to decide how many chargers to build in a new city? Where to place them? Write an equation.
Asked in the onsite stage. Given information about the area, rest points, and walled regions, explain how you would reason about charger count and placement. Keep the answer focused on the decision logic, not implementation details.