paper 2 revision

paper 2 revision

1. Algorithms

   • Describe what is meant by abstraction.
     • Removing unnecessary detail
   • Describe what is meant by decomposition.
     • Breaking down the problem into smaller parts
   • State what is meant by algorithmic thinking.
     • Using logical steps to find a solution to a complex problem.
   • State 2 advantages of a bubble sort
     • - Simple algorithm - Good for short lists

2. Programming techniques

   • State what is meant by casting
     • Temporarily changing the data type of a variable.
   • State the 2 main examples of a sub program
     • Function Procedure
   • State the 5 main data types and their purpose.
     • Character (A single character) - Real (Decimal numbers) - Integer (Whole numbers) - Boolean (True/False) - String (More than 1 character)
   • Describe what is meant by a constant.
     • - A name given for a memory location - Used to store data which cannot change while the program is running.

3. Translators and facilities of languages

   • State the 3 main translators
     • Assembler Compiler Interpreter
   • State the function of a translator
     • To convert high level code to machine code.
   • Describe the error diagnostics function in an IDE
     • Identifies the line where the error is - Suggests ways to fix the error
   • Describe the editor function in an IDE.
     • Allows you write/edit code - Colour codes keywords - Auto completes text

4. Producing robust programs

   • State what is meant by a syntax error
     • An error in the rules/grammar of the language
   • Describe what is meant by a logic error.
     • The error does not prevent the program running - The program does not produce the expected output the programmer intended
   • State what DIV is used for
     • Uses floor division to return an integer value and ignoring the remainder.
   • State what MOD is used for
     • Returns the remainder after division
   • State what is meant by validation
     • Checking that the data meets the requirements / is sensible and reasonable.
   • State what is meant by input sanitisation
     • Removing unwanted characters from an input
   • State the main validation checks used on user inputs
     • Presence check Type check Range check List check Field length check Format check