1A search algorithm
-
arranges elements in ascending order. -
is rarely used with arrays. -
is rarely used with arrays. - is used to locate a specific item in a collection of data.
2Once created, an array size is fixed and cannot be changed.
3A(n) ________ is used as an index to pinpoint a specific element within an array.
- Question 2 options:
subscript - element
- boolean value
- range
4In order to do a binary search on an array
- the values of the array must be numeric.
-
the array must first be sorted. - you must first do a sequential search to be sure the element you are looking for is there.
-
All of these are true
5The Java compiler will display an error message when it processes a statement that uses an invalid subscript.
6The binary search algorithm
-
Will have a maximum number of comparisons equal to the number of elements in the array. -
is less efficient than the sequential search algorithm. - will, normally, have the number of comparisons that is half the number of elements in the array.
-
will cut the portion of the array being searched in half each time it fails to locate the search value.
7The sequential search algorithm
- returns 1 if the value being searched for is found or -1 if the value is not found.
- uses a loop to sequentially step through an array, starting with the first element.
requires the array to be ascending order.- All of these are true
8To determine if two arrays are equal you must compare each of the elements of the two arrays.
9What does the following statement do?
double[] array1 = new double[10];
-
It will allow valid subscripts in the range of 0 through 9. - It declares array1 to be a reference to an array of double values.
- It creates an instance of an array of ten double values.
- It does all of these.
10int [ ] numbers = {50, 10, 15, 20, 25, 100, 30};
int value = 0;
for (int i = 0; i < numbers.length; i++)
value += numbers[i];
- The value variable will contain the sum of all the values in the numbers array.
- The value variable will contain the average of all the values in the numbers array.
- The value variable will contain the lowest value in the numbers array.
- The value variable will contain the highest value in the numbers array.
11What would be the result of executing the following code?
int[] x = {0, 1, 2, 3, 4, 5};
-
An array of 6 values, ranging from 0 through 5 and referenced by the variable x will be created. - The variable x will contain the values 0 through 5.
- A compiler error will occur.
- An array of 6 values, all initialized to 0 and referenced by the variable x will be created.
12When an array is passed to a method
-
the method has direct access to the original array. - it is passed just as any object would be passed
- a reference to the array is passed.
- All of these are true.
13Which of the following statements is(are) true about this code?
final int ARRAY_SIZE = 10;
int[] array1 = new int[ARRAY_SIZE];
- It will allow valid subscripts in the range of 0 through 9.
- It creates an instance of an array of ten int values.
- It declares array1 to be a reference to an array of int values.
- All of these are true.
14What would the output be?
int total = 0;
int [] nums = {40, -9, 100, 1, -15, -90, -78};
for (int x : nums)
if (nums[i] > 0)
total = total + nums[i];
System.out.println(total)
- This will cause an error
- 141
- -192
- 3
15What is this method doing?
public static int doThings (int nums[ ], int x)
{
for (int i = 0; i < nums.length; i++)
if (nums[i] == x)
return i;
return -1;
}
- finding the index of the last positive number in the array
- sorting the array.
- searching for the value of x in the array.
- counting the number of array elements divisible by x.
16The for-each loop is designed to let you look at both the values in an array and their indexes.
17Given an array named arr, which statement(s) would print all the values of the array?
- System.out.println(Arrays.toString(arr));
System.out.println( toString(arr));- System.out.println( arr.toString());
- System.out.println( arr);
18Given the following code, what would be the correct replacement for --Line 1-- to call the doThings method?
public static void main(String[] args)
{
int [] nums = {40, -9, 100, 1, -15, -90, -78, 99};
--- Line 1 -- // statement to call doThings method
}
public static int doThings (int nums[ ])
{
// body of method
}
- int x = doThings(int nums[ ]);
- int x = doThings(int nums);
- int x = doThings(nums);
-
int x = doThings(nums[ ]);