A database containing a sorted index of customer IDs uses a binary search algorithm to locate a specific ID.
Describe how the binary search algorithm operates to locate the target customer ID in the sorted list, explaining how the search space is reduced at each step and how the algorithm determines if the ID is not present.
159 exam-style questions on Edexcel GCSE Computer Science Algorithms, covering Constructs for solving problems, Variables, constants and data structures, Arithmetic, relational and logical operators, Tracing algorithm output with trace tables, Types of error and correcting logic errors, Standard algorithms (sorts and searches), and Evaluating algorithm fitness and efficiency. Each one has a worked solution and a mark scheme showing where the marks go.