Question 1

Assume the method createSomething has been defined as follows:
Int [] createSomething (int start, int size)
{
Int [] result = new int[size];
For (int i = 0; i < result.length; i++)
{
Result[i] = start;
Start++;
}
Return result;
}
What is printed by the statement below?
System.out.print (Arrays.toString(createSomething(4, 3)));

Accepted Answer

The method creates an array of the specified size and fills it with consecutive integers starting from the given start value. Thus, it returns [4, 5, 6] for the input (4, 3).

Question 2

Assume the array of integers values has been created and process is a method that has a single integer parameter. Which of the following is equivalent to the loop below? for (int val: values)
{
Process (val);
}

Accepted Answer

The answer of Assume the array of integers values has...

Question 3

What will be printed by the statements below? ArrayList names = new ArrayList(); Names.add("Annie"); Names.add("Bob"); Names.add("Charles"); For (int i = 0; i < 3; i++) { String extra = names.get(i); Names.add (extra); } System.out.print (names);

Accepted Answer

The loop iterates through the first three elements of the list and adds each element to the end of the list. This results in the list containing duplicates of the first three elements.

Question 4

What will be printed by the statements below?
Int[] values = { 4, 5, 6, 7};
For (int i = 1; i < values.length; i++)
Values[i] = values[i - 1] + values[i];
For (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");

Accepted Answer

The loop starting at line 3 modifies the values array by adding the previous value to the current value. The loop starting at line 6 prints the modified values array.

Question 5

Assume the array of integers values has been created. Which condition must be used in the indicated area so the loop below will assign max the largest value in values?
Int max = values[0];
For (int current = 1; current < values.length; current++)
{
If (/* Put condition here */)
Max = values[current];
}

Accepted Answer

The condition "values[current] > max" ensures that if the current value in the array is greater than the current maximum, the maximum is updated to this new value.

Question 6

The integer array numbers will be filled with the values from the Scanner in. If there are more input values than there are spaces in the array, only enough values to fill the array should be read. The integer variable currentSize should be set to the number of values read. Partial code to do this is given below:
Int[] numbers; // Assume it is created with at least 1 space
Scanner in = new Scanner (System.in);
Int currentSize = 0;
While (/* Put condition here */)
{
Int value = in.nextInt();
Numbers[currentSize] = value;
CurrentSize++;
}
What condition will complete this code?

Accepted Answer

The condition should ensure that the loop continues as long as there is space in the array and there are more integers to read. Therefore, both conditions must be true, which is represented by the logical AND (&&).

Question 7

What will be printed by the statements below? ArrayList names = new ArrayList(); Names.add("Annie"); Names.add("Bob"); Names.add("Charles"); Names.set(2, "Doug"); Names.add(0, "Evelyn"); System.out.print (names);

Accepted Answer

The answer of What will be printed by the statements...

Question 8

What will be printed by the statements below?
Int[] values = { 1, 2, 3, 4};
Values[2] = 24;
Values[values[0]] = 86;
For (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");

Accepted Answer

The answer of What will be printed by the statements...

Question 9

Assume the following variable has been declared and given a value as shown:
Int[][] data = {
{9, 17, -4, 21 },
{15, 24, 0, 9},
{6, 2, -56, 8},
};
Which is the value of data[1][2]?

Accepted Answer

The value of data[1][2] refers to the element in the second row (index 1) and third column (index 2) of the array, which is 0.

Question 10

Assume the following variable has been declared and given a value as shown:
Int[][] data = {
{9, 17, -4, 21 },
{15, 24, 0, 9},
{6, 2, -56, 8},
};
Which is the value of data.length?

Accepted Answer

The value of data.length is 3 because it represents the number of rows in the 2D array 'data'.

Question 11

What will be printed by the statements below?
Int[] values = { 10, 20, 30, 40};
For (int i = 1; i < values.length; i++)
Values[i] = values[i - 1];
For (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");

Accepted Answer

The loop assigns each element the value of the previous element, starting from the second element, resulting in all elements becoming 10.

Question 12

Assume the array of integers values has been created. Which condition must be used in the indicated area so the loop below will assign max the largest value in values?
Int max = values[0];
For (int val: values)
{
If (/* Put condition here */)
Max = val;
}

Accepted Answer

The condition "val > max" ensures that the current value (val) is greater than the current maximum (max), so max is updated to val when this condition is true.

Question 13

Assume the method doSomething has been defined as follows:
Int [] doSomething (int[] values)
{
Int [] result = new int[values.length - 1];
For (int i = 0; i < result.length; i++)
{
Result[i] = values[i] + values[i + 1];
}
Return result;
}
What is printed by the statements below?
Int [] nums = {3, 18, 29, -2} ;
System.out.print (Arrays.toString(doSomething(nums)));

Accepted Answer

The method creates a new array where each element is the sum of consecutive elements from the input array. For the input {3, 18, 29, -2}, the resulting array is {21, 47, 27}.

Question 14

What will be printed by the statements below?
Int[] values = { 4, 5, 6, 7};
Values[0] = values[3];
Values[3] = values[0];
For (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");

Accepted Answer

The answer of What will be printed by the statements...

Question 15

The method findLargest should return the largest of any number of double values. For example, the call findLargest (3.4, -2.6, 2.9) should return 3.4 and the call findLargest (9.2, 17.6, 3.4, -2.6, 2.9) should return 17.6. Partial code to do this is given below: double findLargest (double... values)
{
Double max = values[0];
// New code goes here
Return max;
}
What code will complete this method?

Accepted Answer

The loop iterates over each value in the array, and if a value is greater than the current max, it updates max to that value.

Question 16

Assume the following variable has been declared and given a value as shown:
Int[][] data = {
{9, 17, -4, 21 },
{15, 24, 0, 9},
{6, 2, -56, 8},
};
Which is the value of data[0].length?

Accepted Answer

The value of data[0].length is 4 because it represents the number of elements in the first row of the 2D array, which are 9, 17, -4, and 21.

Question 17

What will be printed by the statements below?
Int[] values = { 10, 24, 3, 64};
Int position = 0;
For (int i = 1; i < values.length; i++)
If (values[i] > values[position])
Position = i;
System.out.print (position);

Accepted Answer

The answer of What will be printed by the statements...

Question 18

What will be printed by the statements below?
Int[] values = { 10, 20, 30, 7};
Int[] numbers = values;
Numbers[2] = 24;
Values[3] = numbers[0] + 6;
System.out.println (numbers[2] + " " + numbers[3] + " "
+ values[2] + " " + values[3]);

Accepted Answer

The arrays `values` and `numbers` reference the same memory location. Changing `numbers[2]` to 24 also changes `values[2]` to 24. Similarly, changing `values[3]` to 16 affects `numbers[3]`. Thus, the output is "24 16 24 16".

Quiz 7: Arrays and Array Lists

Assume the array of integers values has been created and process is a method that has a single integer parameter. Which of the following is equivalent to the loop below? for (int val: values) { Process (val) ; }

What will be printed by the statements below? ArrayList<String> names = new ArrayList<String>() ; Names.add("Annie") ; Names.add("Bob") ; Names.add("Charles") ; For (int i = 0; i < 3; i++) { String extra = names.get(i) ; Names.add (extra) ; } System.out.print (names) ;

What will be printed by the statements below? Int[] values = { 4, 5, 6, 7}; For (int i = 1; i < values.length; i++) Values[i] = values[i - 1] + values[i]; For (int i = 0; i < values.length; i++) System.out.print (values[i] + " ") ;

What will be printed by the statements below? ArrayList<String> names = new ArrayList<String>() ; Names.add("Annie") ; Names.add("Bob") ; Names.add("Charles") ; Names.set(2, "Doug") ; Names.add(0, "Evelyn") ; System.out.print (names) ;

What will be printed by the statements below? Int[] values = { 1, 2, 3, 4}; Values[2] = 24; Values[values[0]] = 86; For (int i = 0; i < values.length; i++) System.out.print (values[i] + " ") ;

Assume the following variable has been declared and given a value as shown: Int[][] data = { {9, 17, -4, 21 }, {15, 24, 0, 9}, {6, 2, -56, 8}, }; Which is the value of data[1][2]?

Assume the following variable has been declared and given a value as shown: Int[][] data = { {9, 17, -4, 21 }, {15, 24, 0, 9}, {6, 2, -56, 8}, }; Which is the value of data.length?

What will be printed by the statements below? Int[] values = { 10, 20, 30, 40}; For (int i = 1; i < values.length; i++) Values[i] = values[i - 1]; For (int i = 0; i < values.length; i++) System.out.print (values[i] + " ") ;

Assume the array of integers values has been created. Which condition must be used in the indicated area so the loop below will assign max the largest value in values? Int max = values[0]; For (int val: values) { If (/* Put condition here */) Max = val; }

What will be printed by the statements below? Int[] values = { 4, 5, 6, 7}; Values[0] = values[3]; Values[3] = values[0]; For (int i = 0; i < values.length; i++) System.out.print (values[i] + " ") ;

Assume the following variable has been declared and given a value as shown: Int[][] data = { {9, 17, -4, 21 }, {15, 24, 0, 9}, {6, 2, -56, 8}, }; Which is the value of data[0].length?

What will be printed by the statements below? Int[] values = { 10, 24, 3, 64}; Int position = 0; For (int i = 1; i < values.length; i++) If (values[i] > values[position]) Position = i; System.out.print (position) ;

What will be printed by the statements below? Int[] values = { 10, 20, 30, 7}; Int[] numbers = values; Numbers[2] = 24; Values[3] = numbers[0] + 6; System.out.println (numbers[2] + " " + numbers[3] + " " + values[2] + " " + values[3]) ;