What this Rust code-reading question tests
This is a medium-difficulty question that asks you to trace the execution of a Rust program and predict its output. It rewards careful attention to ownership, borrowing, and scope—core language semantics that show up frequently in interview rounds at firms that value systems-level correctness.
To answer correctly, you need to follow the logical flow of the code, track how values move or are borrowed through the program, and understand what gets printed at each step. The question is less about memorising syntax and more about building a mental model of how Rust's memory and type system actually behaves at runtime.
- Ownership and move semantics
- Borrowing and references
- Variable shadowing and scope
- String and integer types