Kcats

What this C++ memory and stack behaviour question tests

This is an easy C++ question that probes your understanding of how local variables and the call stack behave at runtime. It asks you to reason about uninitialized memory and predict the most likely outcome when code accesses variables without explicit initialization.

To answer questions like this well, you need to understand stack layout, function call frames, and what values typically reside in memory locations before they are assigned. The question explicitly acknowledges that the behaviour is technically undefined, but rewards candidates who can reason about the likely practical outcome on a typical system without aggressive compiler optimizations.

• Stack frame layout and local variable storage
• Uninitialized vs. zero-initialized memory
• How function calls and returns affect the stack
• The difference between undefined behaviour and probable runtime results