Binary search is asymptotically better than linear

Binary search is asymptotically better than linear search
Asymptotic Algorithm Analysis
Complexity Analysis: Growth of Functions 31 CSCI2100C Data Structures
How to Count Basic Operations in Recursion?
Complexity Analysis: Growth of Functions 32
if left = right
if arr[left]= searchnum
return left
else
return ‐ 1
middle  (left + right)/2
if arr[middle] = searchnum
return middle
elseif arr[middle] < searchnum
return BinarySearch (arr, searchnum, middle+1, right)
else
return BinarySearch (arr, searchnum, left, middle ‐ 1)
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BinarySearch(arr, searchnum, left, right)
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ 1 ሻ
𝑂ሺ ? ሻ
𝑂ሺ ? ሻ
CSCI2100C Data Structures
Worst case analysis of algorithms
Counting the # of basic operations in the
worst case
Big-Oh & Big-Omega notation
Big-Oh & Big-Omega rules (i)-(v)
Asymptotical algorithm comparison
Summary
Complexity Analysis: Growth of Functions 33 CSCI2100C Data Structures
Reading this week
Chapter 3, textbook
Next week
Complexity Analysis: Growth of Functions
with recursions
Recommended Reading
Complexity Analysis: Growth of Functions 34