1) What is the first step in problem-solving? A) Writing code B) Debugging C) Understanding the problem D) Optimizing the solution Answer: C 2) Which of these is not a step in the problem-solving process? A) Algorithm development B) Problem analysis C) Random guessing D) Testing and debugging Answer: C 3) What is an algorithm? A) A high-level programming language B) A step-by-step procedure to solve a problem C) A flowchart D) A data structure Answer: B 4) Which of these is the simplest data structure for representing a sequence of elements? A) Dictionary B) List C) Set D) Tuple Answer: B 5) What does a flowchart represent? A) Errors in a program B) A graphical representation of an algorithm C) The final solution to a problem D) A set of Python modules Answer: B 6) What is pseudocode? A) Code written in Python B) Fake code written for fun C) An informal high-level description of an algorithm D) A tool for testing code Answer: C 7) Which of the following tools is NOT commonly used in pr...
Access Methods
Sequential Access
* A sequential access file copys magnetic tape operation, and generally supports a few operations:
• read next - read a record and advance the tape to the next place.
• write next - write a record and advance the tape to the next place.
• rewind
• skip n records - Might or might not be supported. N may be limited to positive
numbers, or may be limited to +/- 1.
Direct Access
* Jump to any record and read that record. Operations supported include:
• read n - read record number n. ( Note an argument is now needed. )
• write n - write record number n. ( Note an argument is now needed. )
• jump to record n - could be 0 or the endof file.
• Query current record - used to turn back to this record later.
• Sequential access can be easily copied using direct access. The inverse is complicated and inefficient.
Other Access Methods
An indexed access scheme can be easily construct on top of a direct access system. Very large files may need a multi-tiered indexing scheme, i.e. indexes of indexes.
