NR NR507 Week 4 Midterm Exam

Question 24:

The best-case scenario for an insertion sort is –

• The elements are in reverse sorted order
• The elements are already in sorted order (correct answer)
• The elements are in random order
• There is no best-case scenario

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Question 25:

In the Java Class Library, the default constructor Vector creates an empty vector with an initial capacity of –

• 0
• 100
• 10 (correct answer)
• User-defined

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Question 26:

In an array-based chain implementation of a Stack ADT, what is the performance of the ensureCapacity method when the array is not full? –

• O(n)
• O(1) (correct answer)
• O(n log n)
• O(n^2)

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Question 27:

Stacks exhibit which type of behavior? –

• First in, last out
• First in, first out
• Last in, first out (correct answer)
• Last in, first out

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Question 28:

What is the efficiency of the insertion sort method for a chain of n linked nodes? –

• O(2n)
• O(n)
• O(n^2) (correct answer)
• O(n log n)

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Question 29:

The operation to retrieve the top entry of a stack without removing it is called –

• Pop
• Look
• Peek (correct answer)
• Top

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Question 30:

The O(n^2) analysis of insertion sort is a(n) _______ analysis. –

• Worst case (correct answer)
• Best case
• Average case
• Unknown

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Question 31:

What question should you keep in mind when debugging a recursive method? –

• Does each base case produce a result that is correct for that case?
• Are there enough base cases?
• Is at least one of the cases a base case that has no recursive call?
• All of the above (correct answer)

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Question 32:

The precedence of an operator in a postfix expression –

• Is always left-to-right
• Is always right-to-left
• Is implied by the order in which the operators and operands occur (correct answer)
• Depends on the compiler implementation