The learner will review code and answer questions about arrays and for loops.
Arrays
All the flashcards in this set deal with the following code:
int timer = 200;
int digoutPins[] = {0, 1, 2, 3, 4, 5, 6, 7};
int adifferentArray[] = {2, 5, 3, 8, 9};
char thirdArray[30];
int digoutCount = 8;
void setup()
{
for (int PinNum = 0; PinNum < digoutCount; PinNum++)
pinMode(digoutPins[PinNum], OUTPUT);
}
void main()
{
for (int PinNum = 0; PinNum < digoutCount; PinNum++)
{
digitalWrite(digoutPins[PinNum], HIGH);
delay(timer);
digitalWrite(digoutPins[PinNum], LOW);
delay(timer);
}
for (int PinNum = digoutCount - 1; PinNum >- 0; PinNum--)
{
digitalWrite(digoutPins[PinNum], HIGH);
delay(timer);
digitalWrite(digoutPins[PinNum], LOW);
delay(timer);
}
}
This code is displayed in the image below, which will be on each card, but you may want to make note of it before going on.
Question 1 of 10
Arrays
Correct!
All the flashcards in this set deal with the following code:
int timer = 200;
int digoutPins[] = {0, 1, 2, 3, 4, 5, 6, 7};
int adifferentArray[] = {2, 5, 3, 8, 9};
char thirdArray[30];
int digoutCount = 8;
void setup()
{
for (int PinNum = 0; PinNum < digoutCount; PinNum++)
pinMode(digoutPins[PinNum], OUTPUT);
}
void main()
{
for (int PinNum = 0; PinNum < digoutCount; PinNum++)
{
digitalWrite(digoutPins[PinNum], HIGH);
delay(timer);
digitalWrite(digoutPins[PinNum], LOW);
delay(timer);
}
for (int PinNum = digoutCount - 1; PinNum >- 0; PinNum--)
{
digitalWrite(digoutPins[PinNum], HIGH);
delay(timer);
digitalWrite(digoutPins[PinNum], LOW);
delay(timer);
}
}
This code is displayed in the image below, which will be on each card, but you may want to make note of it before going on.
Correct Answer
Got it!
Question 1 of 10
Arrays
Incorrect
All the flashcards in this set deal with the following code:
int timer = 200;
int digoutPins[] = {0, 1, 2, 3, 4, 5, 6, 7};
int adifferentArray[] = {2, 5, 3, 8, 9};
char thirdArray[30];
int digoutCount = 8;
void setup()
{
for (int PinNum = 0; PinNum < digoutCount; PinNum++)
pinMode(digoutPins[PinNum], OUTPUT);
}
void main()
{
for (int PinNum = 0; PinNum < digoutCount; PinNum++)
{
digitalWrite(digoutPins[PinNum], HIGH);
delay(timer);
digitalWrite(digoutPins[PinNum], LOW);
delay(timer);
}
for (int PinNum = digoutCount - 1; PinNum >- 0; PinNum--)
{
digitalWrite(digoutPins[PinNum], HIGH);
delay(timer);
digitalWrite(digoutPins[PinNum], LOW);
delay(timer);
}
}
This code is displayed in the image below, which will be on each card, but you may want to make note of it before going on.
Your Answer
Correct Answer
Got it!
Question 1 of 10
Arrays
In the for loop within the setup function, PinNum has what value at the end of the third loop iteration?
Question 1 of 10
Arrays
Correct!
In the for loop within the setup function, PinNum has what value at the end of the third loop iteration?
Correct Answer
2
PinNum starts that loop with a value of 0 and it is increased by one each time the loop ends. So for the first loop it is 0, for the second loop it is 1, and for the third loop it is 2. (At the beginning of the fourth loop it is incremented to three.)
Question 1 of 10
Arrays
Incorrect
In the for loop within the setup function, PinNum has what value at the end of the third loop iteration?
Your Answer
Correct Answer
2
PinNum starts that loop with a value of 0 and it is increased by one each time the loop ends. So for the first loop it is 0, for the second loop it is 1, and for the third loop it is 2. (At the beginning of the fourth loop it is incremented to three.)
Question 1 of 10
Arrays
Correct!
True or False: Digital pins 0 through 8 are set up as outputs.
Correct Answer
False
Only pins 0 through 7 are set as outputs, the for loop in setup iterates PinNum from 0 to 7 (when it reaches 8 it stops as 8 < 8 is false). So only the pins in the 0 through 7 places in the digoutPins array are set to OUTPUT. Those pin values are 0 through 7.
Question 1 of 10
Arrays
Incorrect
True or False: Digital pins 0 through 8 are set up as outputs.
Your Answer
Correct Answer
False
Only pins 0 through 7 are set as outputs, the for loop in setup iterates PinNum from 0 to 7 (when it reaches 8 it stops as 8 < 8 is false). So only the pins in the 0 through 7 places in the digoutPins array are set to OUTPUT. Those pin values are 0 through 7.
Question 1 of 10
Arrays
Question 1 of 10
Arrays
Correct!
What is the value of the fourth element of the digoutPins array?
Correct Answer
3
The digoutPins array is {0, 1, 2, 3, 4, 5, 6, 7}. Therefore, the fourth element is 3.
Question 1 of 10
Arrays
Incorrect
What is the value of the fourth element of the digoutPins array?
Your Answer
Correct Answer
3
The digoutPins array is {0, 1, 2, 3, 4, 5, 6, 7}. Therefore, the fourth element is 3.
Question 1 of 10
Arrays
True or False: In the first for loop in the main section, PinNum varies from 0 to 8 inclusive and the digital pins 0 through 7 are written to.
Question 1 of 10
Arrays
Correct!
True or False: In the first for loop in the main section, PinNum varies from 0 to 8 inclusive and the digital pins 0 through 7 are written to.
Correct Answer
True
Initially PinNum is 0, and it is incremented until PinNum < digoutCount is false, which happens when PinNum is 8 (since 8 < 8 is false). For each value of PinNum in 0, 1, 2, ..., 7, we perform the digitalWrite command on digoutPins[PinNum]. As digoutPins[0] = 0, digoutPins[1] = 1, ..., digoutPins[7] = 7, we do write to each of the pins 0 through 7 in this for loop.
Question 1 of 10
Arrays
Incorrect
True or False: In the first for loop in the main section, PinNum varies from 0 to 8 inclusive and the digital pins 0 through 7 are written to.
Your Answer
Correct Answer
True
Initially PinNum is 0, and it is incremented until PinNum < digoutCount is false, which happens when PinNum is 8 (since 8 < 8 is false). For each value of PinNum in 0, 1, 2, ..., 7, we perform the digitalWrite command on digoutPins[PinNum]. As digoutPins[0] = 0, digoutPins[1] = 1, ..., digoutPins[7] = 7, we do write to each of the pins 0 through 7 in this for loop.
Question 1 of 10
Arrays
Correct!
The array values must start with the number 0.
Correct Answer
False
The index of the first item in an array is always 0, but the values of the array can be any value (that matches the array's variable type).
Question 1 of 10
Arrays
Incorrect
The array values must start with the number 0.
Your Answer
Correct Answer
False
The index of the first item in an array is always 0, but the values of the array can be any value (that matches the array's variable type).
Question 1 of 10
Arrays
Question 1 of 10
Arrays
Correct!
What is the value of the fourth element of the adifferentArray array?
Correct Answer
8
adifferentArray has values {2, 5, 3, 8, 9} so the value of the fourth element is 8.
Question 1 of 10
Arrays
Incorrect
What is the value of the fourth element of the adifferentArray array?
Your Answer
Correct Answer
8
adifferentArray has values {2, 5, 3, 8, 9} so the value of the fourth element is 8.
Question 1 of 10
Arrays
True or False: The second element of the digoutPins array can be accessed as digoutPins[2].
Question 1 of 10
Arrays
Correct!
True or False: The second element of the digoutPins array can be accessed as digoutPins[2].
Correct Answer
False
digoutPins[2] will give the value of the third element of the digoutPins array since the index for an array starts at 0.
Question 1 of 10
Arrays
Incorrect
True or False: The second element of the digoutPins array can be accessed as digoutPins[2].
Your Answer
Correct Answer
False
digoutPins[2] will give the value of the third element of the digoutPins array since the index for an array starts at 0.
Question 1 of 10
Arrays
Correct!
True or False: The thirdArray array has 30 elements.
Correct Answer
True
When it is initialized in the row char thirdArray[30]; it is set to have 30 elements.
Question 1 of 10
Arrays
Incorrect
True or False: The thirdArray array has 30 elements.
Your Answer
Correct Answer
True
When it is initialized in the row char thirdArray[30]; it is set to have 30 elements.
Question 1 of 10
Arrays
Correct!
What are the indexes of the elements in thirdArray?
Correct Answer
0 - 29
Since thirdArray has 30 elements and the index of an array starts at 0, the indexes of the elements in thirdArray are 0, 1, 2, ..., 28, 29.
Question 1 of 10
Arrays
Incorrect
What are the indexes of the elements in thirdArray?
Your Answer
Correct Answer
0 - 29
Since thirdArray has 30 elements and the index of an array starts at 0, the indexes of the elements in thirdArray are 0, 1, 2, ..., 28, 29.
Question 1 of 10
Arrays
What is the correct way to assign a value to an element of thirdArray?
Question 1 of 10
Arrays
Correct!
What is the correct way to assign a value to an element of thirdArray?
Correct Answer
thirdArray[5] = 'I';
We can assign values to elements of an array that has been initialized by using the assign operation, namely =, by referencing the index of the element we want to change like arrayname[index]. Of the given choices, only one of them has a valid index, namely thirdArray[5] = 'I';
Question 1 of 10
Arrays
Incorrect
What is the correct way to assign a value to an element of thirdArray?
Your Answer
Correct Answer
thirdArray[5] = 'I';
We can assign values to elements of an array that has been initialized by using the assign operation, namely =, by referencing the index of the element we want to change like arrayname[index]. Of the given choices, only one of them has a valid index, namely thirdArray[5] = 'I';
Question 1 of 10
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Arrays by Fox Valley Technical College is licensed under a Creative Commons Attribution 3.0 Unported License.