diff --git a/C++/quicksort.cpp b/C++/quicksort.cpp new file mode 100644 index 0000000..e48fbfc --- /dev/null +++ b/C++/quicksort.cpp @@ -0,0 +1,64 @@ +#include +using namespace std; +// Swap two elements - Utility function +void swap(int* a, int* b) +{ + int t = *a; + *a = *b; + *b = t; +} + +// partition the array using last element as pivot +int partition (int arr[], int low, int high) +{ + int pivot = arr[high]; // pivot + int i = (low - 1); + + for (int j = low; j <= high- 1; j++) + { + //if current element is smaller than pivot, increment the low element + //swap elements at i and j + if (arr[j] <= pivot) + { + i++; // increment index of smaller element + swap(&arr[i], &arr[j]); + } + } + swap(&arr[i + 1], &arr[high]); + return (i + 1); +} + +//quicksort algorithm +void quickSort(int arr[], int low, int high) +{ + if (low < high) + { + //partition the array + int pivot = partition(arr, low, high); + + //sort the sub arrays independently + quickSort(arr, low, pivot - 1); + quickSort(arr, pivot + 1, high); + } +} + +void displayArray(int arr[], int size) +{ + int i; + for (i=0; i < size; i++) + cout<