Searching and Sorting

Question 1

what is binary search

Answer 1

Start at middle position in the list.
If the value at the midpoint is less than the value to be found, the list is divided in half. The lower half of the list is ignored and the search keeps to the upper half of the list.
Otherwise, if the value at the midpoint is greater than the value to be found, the upper half of the list is ignored and the search keeps to the lower half of the list.
The search moves to the midpoint of the remaining items. Steps 2 through 4 continue until a match is made or there are no more items to be found.

Question 2

what is linear search

Answer 2

Find out the length of the data set.
Set counter to 0.
Examine value held in the list at the counter position.
Check to see if the value at that position matches the value searched for.
If it matches, the value is found. End the search.
If not, increment the counter by 1 and go back to step 3 until there are no more items to search.

Question 3

explain the differences of binary and linear search

Answer 3

• linear is much more simpler than binary
• linear is less efficient
• liner is better with small list
• in a ordered list binary list is better as it is suitable for larger lists

Question 4

what is bubble sort

Answer 4

Start at the beginning of the list.
Compare the first value in the list with the next one up. If the first value is bigger, swap the positions of the two values.
Move to the second value in the list. Again, compare this value with the next and swap if the value is bigger.
Keep going until the there are no more items to compare.
Go back to the start of the list.

Question 5

what is a pass in binary search

Answer 5

when you get to the end of the list for the first time

Question 6

what the advantages of bubble sort

Answer 6

• simpler
• efficient to check if in order
• doesn’t use much memory

Question 7

what are disadvantages of bubble sort

Answer 7

• inefficient to sort

- not good with large lists

Question 8

what is merge sort

Answer 8

• split the list in half into sub lists
• keep doing till you get individual items
• each time ur merging sort it
• keep merging and sorting till sub list become one

Question 9

what are advantages of merge sort

Answer 9

• efficient and quicker than bubble sort for large lists

Question 10

what are disadvantages of merge sort

Answer 10

slower for small lists
not good for checking
use lots of memory

Question 11

what is insertion sort

Answer 11

look at second item at list if smaller than first insert in position keep going till all inserted properly

Question 12

what is insertion sort

Answer 12

look at second item at list if smaller than first insert in position keep going till all inserted properly

Question 13

what are advantages of insertion sort

Answer 13

• easy coded
• good with small list
• not much memory
• quick
• easy to check

Question 14

what are disadvantages or insertion sort

Answer 14

not good with large lists