Binary Search GCSE

What is the first step in a binary search algorithm?

• Compare the search item with the last item of the dataset.

• Sort the dataset in ascending order.

• Set the left and right pointers at the beginning and end of the dataset.

• Calculate the midpoint of the dataset.

What condition is necessary for a binary search to work?

• No specific order is required for the data.

• The data must be in ascending order.

• The data must be in descending order.

• The data must be in a random order.

How does a binary search compare to a linear search in terms of efficiency?

• A binary search is more efficient on average.

• A binary search is always less efficient.

• Efficiency depends on the programming language used.

• Both searches have the same efficiency.

What happens if the item you are looking for is greater than the item at the midpoint in a binary search?

• The dataset is re-sorted.

• The search repeats on the left half of the dataset.

• The search ends immediately.

• The search repeats on the right half of the dataset.

What is integer division as used in calculating the midpoint in a binary search?

• Division that rounds down to the nearest whole number.

• Division that includes decimal points.

• Division that returns only the remainder.

• Division that rounds up to the nearest whole number.

In the example provided, what is the initial value of the right pointer?

• 5

• 3

• 7

• 0

What does the binary search algorithm do if the search item is not found at the midpoint?

• It stops the search.

• It repeats the search on the entire dataset.

• It repeats the search on the relevant half of the dataset.

• It randomly selects another midpoint.

What is the main advantage of a binary search over a linear search?

• It does not require the data to be in order.

• It is faster on average.

• It uses less memory.

• It can be used on any type of data.

What is the purpose of the 'found' Boolean flag in the binary search pseudocode?

• To indicate the end of the dataset.

• To determine the midpoint of the dataset.

• To signal that the search item has been found.

• To count the number of items checked.

According to the text, what is not required for understanding binary search algorithms according to the GCSE specification?

• Identifying an algorithm if given the code for it.

• Remembering the code for these algorithms.

• Applying the algorithm to a dataset.

• Understanding the main steps of each algorithm.