Quick sort, a highly efficient sorting algorithm, stands out due to its divide-and-conquer approach. This article delves into implementing quick sort in C, highlighting its efficiency and optimal performance in sorting data.
Understanding the Quick Sort Mechanism
Quick sort operates by selecting a ‘pivot’ element from the array and partitioning the other elements into two sub-arrays, according to whether they are less than or greater than the pivot. The sub-arrays are then sorted recursively.
Implementing Quick Sort in C
The implementation of quick sort in C involves two primary functions: partition() and quickSort(). Here’s a detailed breakdown:
The partition() Function
int partition(int arr[], int low, int high) {
int pivot = arr[high];
int i = (low - 1);
for (int j = low; j <= high- 1; j++) {
if (arr[j] < pivot) {
i++;
swap(&arr[i], &arr[j]);
}
}
swap(&arr[i + 1], &arr[high]);
return (i + 1);
}
The quickSort() Function
void quickSort(int arr[], int low, int high) {
if (low < high) {
int pi = partition(arr, low, high);
quickSort(arr, low, pi - 1);
quickSort(arr, pi + 1, high);
}
}
Auxiliary swap() Function
void swap(int* a, int* b) {
int t = *a;
*a = *b;
*b = t;
}
Key Features of Quick Sort
- Divide and Conquer Strategy: Splits the array and sorts the sub-arrays.
- In-Place Sorting: Does not require additional space.
- Time Complexity: Average and best case – O(n log n), worst case – O(n^2).
Conclusion
Quick sort in C offers a blend of efficiency and speed, making it a go-to choice for sorting large datasets. Understanding and implementing this algorithm enhances your skill set in data structure management and algorithm optimization.
by the Bito team. 
