What is the time complexity of sorting an array using QuickSort on average?
Practice Questions
Q1
What is the time complexity of sorting an array using QuickSort on average?
O(n)
O(n log n)
O(n^2)
O(log n)
Questions & Step-by-Step Solutions
What is the time complexity of sorting an array using QuickSort on average?
Step 1: Understand what time complexity means. It tells us how the time to complete a task grows as the size of the input increases.
Step 2: Know that QuickSort is a sorting algorithm used to arrange elements in an array.
Step 3: Realize that QuickSort works by selecting a 'pivot' element and partitioning the array into two parts: elements less than the pivot and elements greater than the pivot.
Step 4: Understand that the average case occurs when the pivot divides the array into two roughly equal parts.
Step 5: Learn that when the array is divided this way, the sorting process takes log(n) levels of recursion, where n is the number of elements in the array.
Step 6: Each level of recursion processes all n elements, leading to a total time complexity of O(n log n) on average.
Step 7: Conclude that QuickSort is efficient for sorting large arrays because its average time complexity is O(n log n).
