AQA A LEVEL (7517/1) COMPUTER SCIENCE PAPER 1 QUESTION PAPER AND

AQA A LEVEL (7517/1) COMPUTER SCIENCE PAPER 1 QUESTION PAPER AND ANSWERS Strongly Typed - answersWhat type of language is Pascal? This type of language helps to reduce run time errors by forcing declaration of variables & data types, & captialisation. Constant - answersAn item of data whose value DOESN'T change Variable - answersAn item of data whose value COULD change, while being run Algorithm - answersA sequence of steps that can be followed to complete a task in a finite number of steps, always terminates. Element - answersA single value within an array (list) Record - answersOne line of a text file Selection - answersPrinciple of choosing what action to take, based on certain criteria (conditions) - IF & CASE STATEMENTS Nesting - answersPlacing one set of instructions inside another set of instructions Iteration - answersPrinciple of repeating processes - FOR, WHILE, REPEAT UNTIL Definite iteration - answersProcess that repeats a set number of times - FOR LOOP Indefinite Iteration - answersProcess that repeats until a certain criteria is met - WHILE Sequence - answersPrinciple of putting the correct instructions in the right order within a program Truncating - answersProcess of cutting off a number after a certain number of characters or d.p Character Code - answersA unique binary representation of a particular letter, number etc. Subroutine - answersA named block of code designed to carry out a specific task Advantages of subroutines - answersMore readable code Allows code to be reused Allows overloading (changing function based on parameters passed in) Procedure - answersA subroutine which does not return a value to the main program Local Variable - answersA variable that is available only in specified subroutines and functions Advantage of local variables - answersCant inadvertley change value being stored somewhere else; Use same variable name in different sections; Free up memory as when a local variable is finished with it is cleared from memory. Global Variable - answersVariable that is available anywhere in program Function - answersA subroutine that returns a value to the main program Functional programming - answersA programming paradigm that uses functions to create programs - Haskell (also Python in some forms) Hierarchy chart - answersA diagram that shows the design of a system from the top down Top down approach - answersStart at the top of the process and work your way down into smaller and smaller sub processes Why is giving meaningful identifiers good? - answersGood practice, makes more sense, makes program easier to read, easier to debug, helps all different programmers work together on projects etc. Automation - answersCreating a computer model of a real life situation and putting it into action Logical Reasoning - answersUsing a given set of facts to determine whether new facts are true or false Representational abstraction - answersProcess of removing unnecessary details so that only information that is required to solve the problem remains Generalisation abstraction - answersConcept of reducing problems by putting similar aspects of a problem into hierarchical categories Functional Abstraction - answersBreaking own a complex problem into a series of reusable functions Data Abstraction - answersHiding how data is represented so that it is easier to build a new kind of data object Problem Abstraction - answersRemoving unnecessary details in a problem until the underlying problem is identified to see if this is the same as a problem that has already been solved Information Hiding - answersHiding all details of an object that do not contribute to its essential characters Decomposition - answersBreaking down a large task into a series of subtasks Composition - answersBuilding up a whole system from smaller units Finite State Machine - answersAny device that stores it current status and whose status can change as the result of an input. Shown as a state diagram State Transition Diagram - answersA conceptual model to deign and describe system. Useful at the design stage as force designer to think about every possible input. State Transition Table - answersThe logical inputs and outputs of an FSM shown in tabular form What is a state transition diagram? - answersVisual representation of an FSM using circles and arrows, AQA A LEVEL (7517/1) COMPUTER SCIENCE PAPER 1 QUESTION PAPER AND ANSWERS Strongly Typed - answersWhat type of language is Pascal? This type of language helps to reduce run time errors by forcing declaration of variables & data types, & captialisation. Constant - answersAn item of data whose value DOESN'T change Variable - answersAn item of data whose value COULD change, while being run Algorithm - answersA sequence of steps that can be followed to complete a task in a finite number of steps, always terminates. Element - answersA single value within an array (list) Record - answersOne line of a text file Selection - answersPrinciple of choosing what action to take, based on certain criteria (conditions) - IF & CASE STATEMENTS Nesting - answersPlacing one set of instructions inside another set of instructions Iteration - answersPrinciple of repeating processes - FOR, WHILE, REPEAT UNTIL Definite iteration - answersProcess that repeats a set number of times - FOR LOOP Indefinite Iteration - answersProcess that repeats until a certain criteria is met - WHILE Sequence - answersPrinciple of putting the correct instructions in the right order within a program Truncating - answersProcess of cutting off a number after a certain number of characters or d.p Character Code - answersA unique binary representation of a particular letter, number etc. Subroutine - answersA named block of code designed to carry out a specific task Advantages of subroutines - answersMore readable code Allows code to be reused Allows overloading (changing function based on parameters passed in) Procedure - answersA subroutine which does not return a value to the main program Local Variable - answersA variable that is available only in specified subroutines and functions Advantage of local variables - answersCant inadvertley change value being stored somewhere else; Use same variable name in different sections; Free up memory as when a local variable is finished with it is cleared from memory. Global Variable - answersVariable that is available anywhere in program Function - answersA subroutine that returns a value to the main program Functional programming - answersA programming paradigm that uses functions to create programs - Haskell (also Python in some forms) Hierarchy chart - answersA diagram that shows the design of a system from the top down Top down approach - answersStart at the top of the process and work your way down into smaller and smaller sub processes Why is giving meaningful identifiers good? - answersGood practice, makes more sense, makes program easier to read, easier to debug, helps all different programmers work together on projects etc. Automation - answersCreating a computer model of a real life situation and putting it into action Logical Reasoning - answersUsing a given set of facts to determine whether new facts are true or false Representational abstraction - answersProcess of removing unnecessary details so that only information that is required to solve the problem remains Generalisation abstraction - answersConcept of reducing problems by putting similar aspects of a problem into hierarchical categories Functional Abstraction - answersBreaking own a complex problem into a series of reusable functions Data Abstraction - answersHiding how data is represented so that it is easier to build a new kind of data object Problem Abstraction - answersRemoving unnecessary details in a problem until the underlying problem is identified to see if this is the same as a problem that has already been solved Information Hiding - answersHiding all details of an object that do not contribute to its essential characters Decomposition - answersBreaking down a large task into a series of subtasks Composition - answersBuilding up a whole system from smaller units Finite State Machine - answersAny device that stores it current status and whose status can change as the result of an input. Shown as a state diagram State Transition Diagram - answersA conceptual model to deign and describe system. Useful at the design stage as force designer to think about every possible input. State Transition Table - answersThe logical inputs and outputs of an FSM shown in tabular form What is a state transition diagram? - answersVisual representation of an FSM using circles and arrows, AQA A LEVEL (7517/1) COMPUTER SCIENCE PAPER 1 QUESTION PAPER AND ANSWERS Strongly Typed - answersWhat type of language is Pascal? This type of language helps to reduce run time errors by forcing declaration of variables & data types, & captialisation. Constant - answersAn item of data whose value DOESN'T change Variable - answersAn item of data whose value COULD change, while being run Algorithm - answersA sequence of steps that can be followed to complete a task in a finite number of steps, always terminates. Element - answersA single value within an array (list) Record - answersOne line of a text file Selection - answersPrinciple of choosing what action to take, based on certain criteria (conditions) - IF & CASE STATEMENTS Nesting - answersPlacing one set of instructions inside another set of instructions Iteration - answersPrinciple of repeating processes - FOR, WHILE, REPEAT UNTIL Definite iteration - answersProcess that repeats a set number of times - FOR LOOP Indefinite Iteration - answersProcess that repeats until a certain criteria is met - WHILE Sequence - answersPrinciple of putting the correct instructions in the right order within a program Truncating - answersProcess of cutting off a number after a certain number of characters or d.p Character Code - answersA unique binary representation of a particular letter, number etc. Subroutine - answersA named block of code designed to carry out a specific task Advantages of subroutines - answersMore readable code Allows code to be reused Allows overloading (changing function based on parameters passed in) Procedure - answersA subroutine which does not return a value to the main program Local Variable - answersA variable that is available only in specified subroutines and functions Advantage of local variables - answersCant inadvertley change value being stored somewhere else; Use same variable name in different sections; Free up memory as when a local variable is finished with it is cleared from memory. Global Variable - answersVariable that is available anywhere in program Function - answersA subroutine that returns a value to the main program Functional programming - answersA programming paradigm that uses functions to create programs - Haskell (also Python in some forms) Hierarchy chart - answersA diagram that shows the design of a system from the top down Top down approach - answersStart at the top of the process and work your way down into smaller and smaller sub processes Why is giving meaningful identifiers good? - answersGood practice, makes more sense, makes program easier to read, easier to debug, helps all different programmers work together on projects etc. Automation - answersCreating a computer model of a real life situation and putting it into action Logical Reasoning - answersUsing a given set of facts to determine whether new facts are true or false Representational abstraction - answersProcess of removing unnecessary details so that only information that is required to solve the problem remains Generalisation abstraction - answersConcept of reducing problems by putting similar aspects of a problem into hierarchical categories Functional Abstraction - answersBreaking own a complex problem into a series of reusable functions Data Abstraction - answersHiding how data is represented so that it is easier to build a new kind of data object Problem Abstraction - answersRemoving unnecessary details in a problem until the underlying problem is identified to see if this is the same as a problem that has already been solved Information Hiding - answersHiding all details of an object that do not contribute to its essential characters Decomposition - answersBreaking down a large task into a series of subtasks Composition - answersBuilding up a whole system from smaller units Finite State Machine - answersAny device that stores it current status and whose status can change as the result of an input. Shown as a state diagram State Transition Diagram - answersA conceptual model to deign and describe system. Useful at the design stage as force designer to think about every possible input. State Transition Table - answersThe logical inputs and outputs of an FSM shown in tabular form What is a state transition diagram? - answersVisual representation of an FSM using circles and arrows,