Unsigned - Unsigned

What this C++ type-conversion interview question tests

This is a medium-difficulty question on C++ type semantics and implicit conversions, common in quant-firm technical screens. It asks you to trace the behaviour of a program involving unsigned arithmetic and type promotion rules—topics that separate candidates who have read the standard from those who rely on intuition.

To solve problems like this, you need to understand how the C++ type system handles operations between operands of different sizes and signedness. The key is recognizing when operands are promoted, in what order, and what the resulting type will be. Quant firms ask these questions because subtle type bugs can corrupt risk calculations or produce silent data loss in high-frequency systems.

• Integer promotion and the integral conversion hierarchy
• Usual arithmetic conversions between unsigned and signed types
• How operator precedence and associativity interact with type rules
• Platform-dependent behaviour and the role of sizeof