Question

1. The table below contains a program and a sample input, complete the table by writing the output that will result from the input. [Be careful and follow every line as it would execute on a computer, don't assume you can just guess how the game works, unless you do know snooker.]

2. List the counters and accumulators (if any) in the program, briefly explain why you think each is a counter or accumulator.

input:

O'Sullivan
red

green

red

pink

red

none

Program Input Output? start num RED POINTS 1 num YELLOW POINTS2 num GREEN POINTS 3 num BROWN POINTS 4 num BLUE PONTS 5 num PINK POINTS 6 num BLA INTS 7 num redCont a n num yolowCount 0 num groan num brown num bluaCourt-n num pinkCount e o num biackCourt :0 num coio t0 num score aD. string baIRoted boolean tailadToPat tase oriome innué plavartNanme whie NOTtaledToPot) input baliPotted balPotted rad adCount radCount+ 1 scora scone + RED PONTS gise balPot d"yelow yelowCount yelowCount+1 calorCount colorCount+1 scora scom + YELLOW POINTS lpSu224van oise balPotted "graan" encount+1 colarCount scare score GREEN POINTS aisa balPoted brown biwco.nt= BrownCount+ 1 colorCount colorCount+ score score + BROWN POINTS balPotted"biue bluecount blueCount+ 1 calorCount cold one score BLUE PONTS gise if balPotod "pink pinkCount pinkCount+ 1 colorCaunt colorCount 1 scone score PINK POINTS cise balPoted black blackCount colorCount colorCount+ 1 ackCoune scorescore+ BLACK POINTS autput plaverName autput score adToPot true endit dh dit codt ondis andif andahila output "Coior bals potted:, colorount stoo

start

    num RED_POINTS = 1
    num YELLOW_POINTS = 2
    num GREEN_POINTS = 3
    num BROWN_POINTS = 4
    num BLUE_POINTS = 5
    num PINK_POINTS = 6
    num BLACK_POINTS = 7

    num redCount = 0

    num yellowCount = 0

    num greenCount = 0

    num brownCount = 0

    num blueCount = 0

    num pinkCount = 0

    num blackCount = 0
    num colorCount = 0
    num score = 0
    string ballPotted
    boolean failedToPot = false
    string playerName
    input playerName
    while NOT(failedToPot)
        input ballPotted
        if ballPotted = "red"
            redCount = redCount + 1
            score = score + RED_POINTS
        else
            if ballPotted = "yellow"
                yellowCount = yellowCount + 1
                colorCount = colorCount + 1
                score = score + YELLOW_POINTS
            else
                if ballPotted = "green"
                    greenCount = greenCount + 1
                    colorCount = colorCount + 1
                    score = score + GREEN_POINTS
                else
                    if ballPotted = "brown"
                        browCount = brownCount + 1
                        colorCount = colorCount + 1
                        score = score + BROWN_POINTS
                    else
                        if ballPotted = "blue"
                            blueCount = blueCount + 1
                            colorCount = colorCount + 1
                            score = score + BLUE_POINTS
                        else
                            if ballPotted = "pink"
                                pinkCount = pinkCount + 1
                                colorCount = colorCount + 1
                                score = score + PINK_POINTS
                            else
                                if ballPotted = "black"
                                    blackCount = blackCount + 1
                                    colorCount = colorCount + 1
                                    score = score + BLACK_POINTS
                                else
                                    output playerName

                                    output score

                                    failedToPot = true
                                endif
                            endif
                        endif
                    endif
                endif
            endif 
        endif
    endwhile
    output "Color balls potted: ", colorCount

stop

Answer 1

I'm gonna start explaining the program and every input to you one by one so just keep the code at one side and read this answer. The actual lines of code are in bold and each line of my explanation is normal text.

Start // Here the program just starts

So, the next few lines they’ve declared a bunch of variables and assigned some value to some of them.

    num RED_POINTS = 1 // declaring and initialising a number variable RED_POINTS to value 1

    num YELLOW_POINTS = 2 // declaring and initialising a number variable YELLOW_POINTS to value 2

    num GREEN_POINTS = 3 // declaring and initialising a number variable GREEN_POINTS to value 3

    num BROWN_POINTS = 4 // declaring and initialising a number variable BROWN_POINTS to value 4

    num BLUE_POINTS = 5 // declaring and initialising a number variable BLUE_POINTS to value 5

    num PINK_POINTS = 6 // declaring and initialising a number variable PINK_POINTS to value 6

   num BLACK_POINTS = 7 // declaring and initialising a number variable BLACK_POINTS to value 7

    num redCount = 0 // declaring and initialising a number variable redCount to value 0

    num yellowCount = 0 // declaring and initialising a number variable yellowCount to value 0

  num greenCount = 0 // declaring and initialising a number variable greenCount to value 0

    num brownCount = 0 // declaring and initialising a number variable brownCount to value 0

    num blueCount = 0 // declaring and initialising a number variable blueCount to value 0

    num pinkCount = 0 // declaring and initialising a number variable pinkCount to value 0

    num blackCount = 0 // declaring and initialising a number variable blackCount to value 0

    num colorCount = 0 // declaring and initialising a number variable colorCount to value 0

    num score = 0 // Setting a number variable score to value 0

    string ballPotted // declaring a string ballPotted

    boolean failedToPot = false // declaring a boolean failedToPot to false

    string playerName // decalring a string playerName

    input playerName // taking input playerName. Here the first input O'Sullivan is taken as input and stored in the variable playerName

So, now there’s a while loop which will keep going if the value of failedToPot is false. As the initial value of failed to pot is false and the NOT makes it true the loop with start.

    while NOT(failedToPot) // starting the loop

        input ballPotted // taking input and storing in variable ballPotted

        if ballPotted = "red" //if the input is red then enter the if statement

            redCount = redCount + 1 // increase the variable redCount by 1

            score = score + RED_POINTS // update variable score to score + RED_POINTS

        else

            if ballPotted = "yellow" //if the input is not red but yellow then enter the else if statement

                yellowCount = yellowCount + 1 // increase the variable yellowCount by 1

                colorCount = colorCount + 1 // increase the variable colorCount by 1

                score = score + YELLOW_POINTS // update variable score to score + YELLOW_POINTS

            else

                if ballPotted = "green" //if the input is neither red or yellow but green then enter the else if statement

                    greenCount = greenCount + 1 // increase the variable greenCount by 1

                    colorCount = colorCount + 1 // increase the variable colorCount by 1

                    score = score + GREEN_POINTS // update variable score to score + GREEN_POINTS

                else

                    if ballPotted = "brown" //if the input is neither red, yellow or green but brown then enter the else if statement

                        browCount = brownCount + 1 // increase the variable brownCount by 1

                        colorCount = colorCount + 1 // increase the variable colorCount by 1

                        score = score + BROWN_POINTS // update variable score to score + BROWN_POINTS

                    else

                        if ballPotted = "blue" //if the input is neither red, yellow, green or brown but blue then enter the else if statement

                            blueCount = blueCount + 1 // increase the variable blueCount by 1

                            colorCount = colorCount + 1 // increase the variable colorCount by 1

                            score = score + BLUE_POINTS // update variable score to score + BLUE_POINTS

                        else

                           if ballPotted = "pink" //if the input is neither red, yellow, green, brown or blue but pink then enter the else if statement

                                pinkCount = pinkCount + 1 // increase the variable pinkCount by 1

                                colorCount = colorCount + 1 // increase the variable colorCount by 1

                                score = score + PINK_POINTS // update variable score to score + PINK_POINTS

                            else

                                if ballPotted = "black" //if the input is neither red, yellow, green, brown, blue or pink but black then enter the else if statement

                                    blackCount = blackCount + 1 // increase the variable blackCount by 1

                                    colorCount = colorCount + 1 // increase the variable colorCount by 1

                                    score = score + BLACK_POINTS // update variable score to score + BLACK_POINTS

                                else //if the input is anything except red, yellow, green, brown, blue, pink or black then enter the else statement

                                    output playerName // output the playerName variable

                                    output score // output the score variable

                                    failedToPot = true // set the failedToPot variable to true.

                                Endif // now the program closes all the if statements one by one.

                            Endif // closing if

                        endif // closing if

                    endif // closing if

                endif // closing if

            endif // closing if

        endif // closing if

    endwhile // end of the while loop

    output "Color balls potted: ", colorCount // output the text “Color balls potted: ” followed by the variable colorCount

stop // the program stops here.

The first input (O’Sullivan): This program first takes in the name of the player in the input.

Second Input (red): This input is inside the while loop. And it matches the condition of one of the if statements so it goes inside the if statement and increases redCount(0) by 1, so redCount now = 1. And updates the score(0) by score(0) + RED_POINTS(1), so score = 1 now.

Third Input (green): This input is again inside the while loop. And it matches the condition of one of the if statements so it goes inside the if statement and increases greenCount(0) by 1, so greenCount now = 1. It also increases the colorCount(0) by 1, so colorCount now = 1. And updates the score(1) by score(1) + GREEN_POINTS(3), so score = 4 now.

Fourth Input (red): This input is again inside the while loop. And it matches the condition of one of the if statements so it goes inside the if statement and increases redCount(1) by 1, so redCount now = 2. And updates the score(4) by score(4) + RED_POINTS(1), so score = 5 now.

Fifth Input (pink): This input is again inside the while loop. And it matches the condition of one of the if statements so it goes inside the if statement and increases pinkCount(0) by 1, so pinkCount now = 1. It also increases the colorCount(1) by 1, so colorCount now = 2. And updates the score(5) by score(5) + PINK_POINTS(6), so score = 11 now.

Sixth Input (red): This input is again inside the while loop. And it matches the condition of one of the if statements so it goes inside the if statement and increases redCount(2) by 1, so redCount now = 3. And updates the score(11) by score(11) + RED_POINTS(1), so score = 12 now.

Seventh Input (none): This input is again inside the while loop but it does not match the conditions of any of the if statements, so it goes inside the else statement and output the variable playerName. Then it outputs the variable score. And finally sets the failedToPot variable to true.

Next time the while loop runs the failedToPot variable is set to true and the NOT will turn it into false. So the while loop ends and the following line executes:

output "Color balls potted: ", colorCount

This line outputs the text “Color balls potted: “ followed by the variable colorCount. And the program ends here.

So, the final output is:

O’Sullivan

12

Color balls potted: 2