What is Big O Notation?
Big O notation is a mathematical notation that describes the limiting behavior of a function when the argument tends towards a particular value or infinity. In computer science, it's used to classify algorithms according to how their run time or space requirements grow as the input size (n) grows. It describes the **worst-case scenario** and provides an upper bound on the growth rate.
Common Complexities
| Notation |
Name |
Example |
| O(1) | Constant | Accessing an array element by index. |
| O(log n) | Logarithmic | Binary Search in a sorted array. |
| O(n) | Linear | Finding an item in an unsorted list (Linear Search). |
| O(n log n) | Log-Linear | Efficient sorting algorithms like Merge Sort. |
| O(n²) | Quadratic | Simple sorting algorithms like Bubble Sort. |
| O(2ⁿ) | Exponential | Recursive calculation of Fibonacci numbers. |
| O(n!) | Factorial | Solving the Traveling Salesman Problem via brute-force. |
