Question 1

The code segment below displays a table of numbers. Select an expression to complete the code segment, so that the resulting algorithm has O(n2) running time. for (int k = 1; k <= n; k++)
{
For _______________________
{
System.out.print(j + " ");
}
System.out.println();
}

Accepted Answer

A)  (int j = n; j > 0; j = j / 2) 
B)  (int j = 1; j < k; j = j * 2) 
C)  (int j = 0; j < k; j++) 
D)  (int j = 1; j <= 200; j++)

Question 2

In the worst case, quicksort is a(n) ____ algorithm.

Accepted Answer

A)  O(n) 
B)  O(log(n)) 
C)  O(n2) 
D)  O(n log n)

Question 3

Suppose an array has n elements. We visit element #1 one time, element #2 two times, element #3 three times, and so forth. How many total visits will there be?

Accepted Answer

A)  2n 
B)  n(n+1)/2 
C)  n2 
D)  n3

Question 4

An algorithm that tests whether the first array element is equal to any of the other array elements would be an ____ algorithm.

Accepted Answer

A)  O(1) 
B)  O(n) 
C)  O(log (n)) 
D)  O(n log (n))

Question 5

Which selection sort iteration guarantees the array is sorted for a 10-element array?

Accepted Answer

A)  9th iteration 
B)  10th iteration 
C)  1st iteration 
D)  impossible to tell

Question 6

Suppose we are using binary search on an array with approximately 1,000,000 elements. How many visits should we expect to make in the worst case?

Accepted Answer

A)  1 
B)  16 
C)  20 
D)  30

Question 7

Which of the sorts in the textbook can be characterized by the fact that the best case will have a running time of θ(n) if the data is already sorted?
I quicksort
II selection sort
III insertion sort

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  I and III

Question 8

If the array is already sorted, what is the performance of insertion sort?

Accepted Answer

A)  O(n) 
B)  O(n2) 
C)  O(log n) 
D)  O(n log n)

Question 9

What is the smallest value of n for which n2 > 3n + 4?

Accepted Answer

A)  6 
B)  5 
C)  4 
D)  3

Question 10

Consider the sort method for selection sort shown below: public static void sort (int[]A) An exception would occur

Accepted Answer

A)  {
For (int i = 0; i < a.length - 1; i++)
{
Int minPos = minimumPosition(i);
Swap(minPos, i);
}
}
Suppose we modify the loop control to read int i = 1; i < a.length - 1; i++. What would be the result? 
B)  The sort would not consider the last array element. 
C)  The sort would not consider the first array element. 
D)  The sort would still work correctly.

Question 11

What is the worst-case performance of insertion sort?

Accepted Answer

A)  O(n) 
B)  O(n2) 
C)  O(log (n)) 
D)  O(n log (n))

Question 12

Consider the sort method shown below for selection sort: public static void sort (int[]A) An exception would occur.

Accepted Answer

A)  {
For (int i = 0; i < a.length - 1; i++)
{
Int minPos = minimumPosition(i);
Swap(minPos, i);
}
}
Suppose we modify the call to the swap method call to read swap(i, minPos). What would be the result? 
B)  The sort would produce incorrect results. 
C)  The sort would work, but sort backwards. 
D)  The sort would produce correct results.

Question 13

If a call to the Arrays static method binarySearch returns a value of 7, what can be concluded?
I the element is not in the array
II the element is at index 7
III the element occurs 7 times in the array

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  II and III

Question 14

What type of algorithm places elements in order?

Accepted Answer

A)  sorting 
B)  searching 
C)  insertion 
D)  deletion

Question 15

In big-Oh notation, suppose an algorithm requires an order of n3 element visits. How does doubling the number of elements affect the number of visits?

Accepted Answer

A)  It doubles the number of visits. 
B)  It quadruples the number of visits. 
C)  It triples the number of visits. 
D)  It number of visits goes up by a factor of eight.

Question 16

Consider the swap method shown below from the SelectionSorter class. If we modified it as shown in the swap2 method shown below, what would be the effect on the sort method? private static void swap(int[] a, int i, int j)
{
Int temp = a[i];
A[i] = a[j];
A[j] = temp;
}
Private static void swap2(int[] a, int i, int j)
{
A[i] = a[j];
A[j] = a[i];
}

Accepted Answer

A)  There would be no effect. 
B)  Some array elements would be overwritten. 
C)  It would sort the array in reverse order. 
D)  It would still be correct, but run a little faster.

Question 17

Suppose objects a and b are from a user-defined class that implements the Comparable interface. Which condition tests the compareTo method's return value to determine that a will precede b when the sort method is called?

Accepted Answer

A)  a.compareTo(b) == -1 
B)  a.compareTo(b) == 0 
C)  a.compareTo(b)  0

Question 18

Another name for linear search is ____ search.

Accepted Answer

A)  sorted 
B)  sequential 
C)  random 
D)  binary

Question 19

In the textbook, we determined that the merge method requires a total of 5n visits. We found that the number of visits required to sort an array of n elements is T(n) = T(n / 2) + T(n / 2) + 5n. What does T(n / 2) describe?

Accepted Answer

A)  the total number of visits to merge sort an array of n elements 
B)  half the number of visits to merge sort an array of n elements 
C)  the total number of visits to merge sort an array of n / 2 elements 
D)  half the number of visits to merge sort an array of n / 2 elements

Question 20

Which sort algorithm starts by partitioning the array and selecting a pivot element?

Accepted Answer

A)  merge sort 
B)  quicksort 
C)  selection sort 
D)  insertion sort

Exam 14: Sorting and Searching

The code segment below displays a table of numbers. Select an expression to complete the code segment, so that the resulting algorithm has O(n²) running time. for (int k = 1; k <= n; k++) { For _______________________ { System.out.print(j + " ") ; } System.out.println() ; }

In the worst case, quicksort is a(n) ____ algorithm.

Suppose an array has n elements. We visit element #1 one time, element #2 two times, element #3 three times, and so forth. How many total visits will there be?

An algorithm that tests whether the first array element is equal to any of the other array elements would be an ____ algorithm.

Which selection sort iteration guarantees the array is sorted for a 10-element array?

Suppose we are using binary search on an array with approximately 1,000,000 elements. How many visits should we expect to make in the worst case?

Which of the sorts in the textbook can be characterized by the fact that the best case will have a running time of θ(n) if the data is already sorted? I quicksort II selection sort III insertion sort

If the array is already sorted, what is the performance of insertion sort?

What is the smallest value of n for which n² > 3n + 4?

Consider the sort method for selection sort shown below: public static void sort (int[]A) An exception would occur

What is the worst-case performance of insertion sort?

Consider the sort method shown below for selection sort: public static void sort (int[]A) An exception would occur.

If a call to the Arrays static method binarySearch returns a value of 7, what can be concluded? I the element is not in the array II the element is at index 7 III the element occurs 7 times in the array

What type of algorithm places elements in order?

In big-Oh notation, suppose an algorithm requires an order of n³ element visits. How does doubling the number of elements affect the number of visits?

Suppose objects a and b are from a user-defined class that implements the Comparable interface. Which condition tests the compareTo method's return value to determine that a will precede b when the sort method is called?

Another name for linear search is ____ search.

In the textbook, we determined that the merge method requires a total of 5n visits. We found that the number of visits required to sort an array of n elements is T(n) = T(n / 2) + T(n / 2) + 5n. What does T(n / 2) describe?

Which sort algorithm starts by partitioning the array and selecting a pivot element?

Exam 14: Sorting and Searching

The code segment below displays a table of numbers. Select an expression to complete the code segment, so that the resulting algorithm has O(n2) running time. for (int k = 1; k <= n; k++) { For _______________________ { System.out.print(j + " ") ; } System.out.println() ; }

In the worst case, quicksort is a(n) ____ algorithm.

Suppose an array has n elements. We visit element #1 one time, element #2 two times, element #3 three times, and so forth. How many total visits will there be?

An algorithm that tests whether the first array element is equal to any of the other array elements would be an ____ algorithm.

Which selection sort iteration guarantees the array is sorted for a 10-element array?

Suppose we are using binary search on an array with approximately 1,000,000 elements. How many visits should we expect to make in the worst case?

Which of the sorts in the textbook can be characterized by the fact that the best case will have a running time of θ(n) if the data is already sorted? I quicksort II selection sort III insertion sort

If the array is already sorted, what is the performance of insertion sort?

What is the smallest value of n for which n2 > 3n + 4?

Consider the sort method for selection sort shown below: public static void sort (int[]A) An exception would occur

What is the worst-case performance of insertion sort?

Consider the sort method shown below for selection sort: public static void sort (int[]A) An exception would occur.

If a call to the Arrays static method binarySearch returns a value of 7, what can be concluded? I the element is not in the array II the element is at index 7 III the element occurs 7 times in the array

What type of algorithm places elements in order?

In big-Oh notation, suppose an algorithm requires an order of n3 element visits. How does doubling the number of elements affect the number of visits?

Suppose objects a and b are from a user-defined class that implements the Comparable interface. Which condition tests the compareTo method's return value to determine that a will precede b when the sort method is called?

Another name for linear search is ____ search.

In the textbook, we determined that the merge method requires a total of 5n visits. We found that the number of visits required to sort an array of n elements is T(n) = T(n / 2) + T(n / 2) + 5n. What does T(n / 2) describe?

Which sort algorithm starts by partitioning the array and selecting a pivot element?

The code segment below displays a table of numbers. Select an expression to complete the code segment, so that the resulting algorithm has O(n²) running time. for (int k = 1; k <= n; k++) { For _______________________ { System.out.print(j + " ") ; } System.out.println() ; }

What is the smallest value of n for which n² > 3n + 4?

In big-Oh notation, suppose an algorithm requires an order of n³ element visits. How does doubling the number of elements affect the number of visits?