# What is best worst and average case complexity explain with example?

## What is best worst and average case complexity explain with example?

Best case is the function which performs the minimum number of steps on input data of n elements. Worst case is the function which performs the maximum number of steps on input data of size n. Average case is the function which performs an average number of steps on input data of n elements.

## What are the best average and worst case time complexities of selection sort?

Worst case = Average Case = Best Case = O(n log n) The total time complexity sums up to O(log n) + O(log (n -1)) + … + O(1) = O(log (n!)). The time complexity of O(n log n) best represents this complexity in a simplified form.

**Which sorting algorithm is best in worst case?**

If you’ve observed, the time complexity of Quicksort is O(n logn) in the best and average case scenarios and O(n^2) in the worst case. But since it has the upper hand in the average cases for most inputs, Quicksort is generally considered the “fastest” sorting algorithm.

### What is worst case complexity example?

In computer science (specifically computational complexity theory), the worst-case complexity measures the resources (e.g. running time, memory) that an algorithm requires given an input of arbitrary size (commonly denoted as n in asymptotic notation). It gives an upper bound on the resources required by the algorithm.

### Which of the following algorithm has same time complexity in best average and worst case?

Heap sort – Best, average and worst case time complexity: nlogn which is independent of distribution of data.

**Which of the following algorithm have same time complexity in best average and worst case?**

Time Complexities of all Sorting Algorithms

Algorithm | Time Complexity | |
---|---|---|

Best | Worst | |

Insertion Sort | Ω(n) | O(n^2) |

Heap Sort | Ω(n log(n)) | O(n log(n)) |

Quick Sort | Ω(n log(n)) | O(n^2) |

#### Which of the following algorithms has the lowest best and worst case complexity?

ANSWER: Merge sort The merge sort uses the weak complexity their complexity is shown as O(n log n).

#### What is the average case complexity of bubble sort *?

Bubble sort may require (n/2) passes and O(n) comparisons for each pass in the average case. As a result, the average case time complexity of bubble sort is O(n/2 x n) = O(n/2 x n) = O(n/2 x n) = O(n/2 x n) = O (n2).

**Which of the following sorting algorithm has the lowest worst case complexity?**

## What is the best case average case and worst case of merge sort algorithm?

Merge sort

An example of merge sort. First, divide the list into the smallest unit (1 element), then compare each element with the adjacent list to sort and merge the two adjacent lists. Finally, all the elements are sorted and merged. | |
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Class | Sorting algorithm |

Data structure | Array |

Worst-case performance |