Linear & Binary Search
Unit 3 Summary - part 4
Linear Search
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Searches from the beginning, one by one
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Advantage: Can search unsorted list.
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Disadvantage: Slow to search if there are many items in the list.
If Linear Search were made into a Spanish dance,
it would look like this:
Binary Search
Searches from the middle and ignores the rest of the list
(if it's lower/higher than what we're looking for)
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Advantage: Very fast to search if we have so many items (because it ignores the rest if it's lower/higher than what we're looking for).
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Disadvantage: The list needs to be sorted first. Not so fast if we only have few items in the list.
If Binary Search were a flamenco dance, it would be entertaining:
Oxford AQA IGCSE Specimen paper
10.
Figure 8 shows a list of names stored in an array called Names.
Figure 8
Names
10.1.
If a linear search is being used to try and find the name “Ray” in the Names array how many comparisons will be made? [1 mark]
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__________________________________________________________________________________
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Answer:
7
10.2.
If a binary search is being used to try and find the name “Ray” in the Names array how many comparisons will be made? [1 mark]
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__________________________________________________________________________________
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Answer:
2
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10.3.
For each statement shade in a box to show if the statement is true or false.
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Statement
Answers:
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False;
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False;
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True;
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False;
