The document discusses and compares linear and binary search algorithms. Linear search sequentially checks each element of an unsorted array to find a target value, while binary search works on a sorted array by repeatedly calculating the midpoint and comparing the target to the value there to narrow the search range. It provides steps for performing a binary search, including sorting the array, calculating the midpoint, and updating the search range based on whether the target is less than, greater than, or equal to the midpoint value.

1. SearchSearch
Linear & Binary

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Linear Search
• Find 37?
≠ ≠ =
Return 2

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Binary Search
• Find 37?
1. Sort Array.

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Binary Search
2. Calculate middle = (low + high) / 2.
= (0 + 8) / 2 = 4.
If 37 == array[middle]  return middle
Else if 37 < array[middle]  high = middle -1
Else if 37 > array[middle]  low = middle +1

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Binary Search
Repeat 2. Calculate middle = (low + high) / 2.
= (0 + 3) / 2 = 1.
If 37 == array[middle]  return middle
Else if 37 < array[middle]  high = middle -1
Else if 37 > array[middle]  low = middle +1

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Binary Search
Repeat 2. Calculate middle = (low + high) / 2.
= (2 + 3) / 2 = 2.
If 37 == array[middle]  return middle
Else if 37 < array[middle]  high = middle -1
Else if 37 > array[middle]  low = middle +1

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Binary Search

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Binary Search
• If not found  stop when low > high.