CS Prelim I

State the standard algorithm used in a program above?

• Traversing an array

• Input Validation

• Running Total

• Variable Assignment

There are 20 pupils in N5 Computing class. The teacher wants to use a loop to enter the pupils' marks into a program. State the type of loop that the teacher would use and explain why.

• Fixed loop, because the teacher would type only 20 marks for 20 pupils in his class.

• Conditional loop, because the Teacher will finish typing the marks in after the last pupil.

• Fixed loop because it will repeat the code only for a certain amount of time.

• Conditional loop because the code will be repeated until the condition is met.

Explain what is a wireframe used in program design?

• The wireframe shows the user how the program might look at the end of the process.

• It is used to plan the location of elements/objects used and the overall layout of the user interface.

Software developers often have to return to the implementation stage of an iterative development process following the testing stage. Explain why this is.

• Correct any errors encountered and identified during the testing stage and modify the code accordingly.

• To add extra features into the code which were proposed to be added after the test runs.

• In case of any errors.

• To make changes.

Explain how a bit mapped graphic is saved in computer's memory?

• Bit-mapped graphics are stored in a computer's memory as a map of the grid.

• Each grid is called a pixel, which is represented by the binary value stored as 1s and 0s.

• Every pixel has a binary value assigned, which represents the colour it holds.

• Map of pixels with bits.

State the part of the processor that temporarly stores pupils' grade.

• Registers

• Arithmetic and Logic Unit

• Control Unit

• Data Bus

State the part of the processor that calculates the average grade.

• Registers

• Arithmetic and Logic Unit

• Control Unit

• Address Bus

When executing the program it is translated into binary. Why does a high-level language need to be translated into binary?

• A high-level language is a language used and recognized by humans.

• The program is translated into machine code for the computer to understand the code, as the only values it can recognize are 1s and 0s.

• It is the only thing computer understands.

• Computer only read machine code.

Describe one advantage of using an interpreter and one advantage of using a compiler when translating code.

• The interpreter translates one line of code at a time, and as soon as it encounters the error - it is communicated to the user.

• The interpreter translates one line of code a time and communicates the presence of an error as soon as it is encountered allowing for the quick fix of errors and preventing replicating them.

• The compiler runs faster than the translator as it only translates the program once and saves it as an object code.

• When using compiler, the code itself is not needed to run the program because the translation of code and execution code are two separate processes.

Explain how a bit-mapped graphic is saved in the computer's memory.

• Bit mapped graphics are being stored in a computer's memory as a map of grid.

• Each grid is called pixel which is represented by the binary value stored as a 1s and 0s.

• Every pixel has a binary value assigned which represent the colour it holds.

• Map of pixels with bits in it.