GCSE revision questions (self created)

How many different values can be represented with 7 bits?

• 127
• 128
• 64
• 255

What is a DISADVANTAGE of binary search?

• Is more inefficient than linear search
• Is more efficient than linear search
• Requires the data to be sorted
• Requires the data to NOT be sorted

Which of the following best describes Merge Sort?

• Annoying and complicated
• Divide-and-conquer
• Inefficient

What would this sequence look like after two full passes of the bubble sort algorithm: 70, 99, 3, 7, 96, 4

• 3, 7, 4, 70, 96, 99

• 70, 3, 99, 7, 96, 4

• 70, 3, 7, 96, 99, 4

• 3, 7, 70, 4, 96, 99

Which of the following is true about the AND operator in programming languages?

• It evaluates to true if either operand is true.
• It evaluates to true only if both operands are true.
• It evaluates to false if either operand is false.
• It evaluates to false only if both operands are false.

Which sorting algorithm is this?

1. Start at the beginning of the list.

2. Compare the values in positions 1 and 2 of the list - if they are not in ascending order then swap them.

3. Compare the values in positions 2 and 3 of the list and swap if necessary.

4. Continue to the end of the list.

5. If there have been any swaps, go back to step 1.

6. If there have not been any swaps, the list is sorted.

• merge

• linear

• bubble

• binary

What sorting algorithm is this?

1. Select the median item in the list (if there are an even number of elements, round down, i.e select the element left of centre).

2. If the median item is equal to the search item, then stop searching and return item is found.

3. If the median item is higher than the search item then repeat steps 1 and 2 with the sub-list to the left.

4. If the median item is lower than the search item then repeat steps 1 and 2 with the sub-list to the right.

5. Repeat steps 3 and 4 unless the sub-list is empty.

6. If the sub-list is empty, stop searching and return item not found.

• merge

• linear

• bubble

• binary

Why would RLE not be useful for compressing a text file

• Because it takes too long
• Because it is too demanding on the computer parts
• Because the file size would likely increase
• Because it uses too much energy

Convert 172 kibibytes to bytes.

• 176128 bytes

• 172000 bytes

• 0.172 bytes

• 174926 bytes

In comparison to unsigned binary integers, how many values can signed binary integers store with the same number of bits

• half as much

• the same

• double

• 7