AnthropicVerified interview challenge
Repair a looping bootloader program
Trace a small instruction program, repair its loop and explain the result of a concurrent search.
Unlock with Full AccessThe challenge
A small program changes an accumulator and moves between instructions, but its control flow enters a loop. First model its execution, then find the single instruction change that lets it terminate correctly.
Later work uses the supplied executor to search for a repair and asks you to explain the result. Keep the original program intact as you reason about valid termination, repeated instructions and candidate changes.
What you'll practise
Execution modelling
Track state and termination conditions without mutating the supplied program.
Repair search
Find a valid instruction change and reason about the concurrent search result.
Current partFurther parts unlock as you progress
solution.pyPython 3.13
# Build on your implementation
# Run checks for the current part
# Full starter code includedCurrent-part checks
Run your code to see results.
The complete sequence, starter code and checks are included with Full Access.