Iterative_quick_sort.cpp

 #include <iostream> 
using namespace std; 

// Function to swap numbers 
void swap(int* a, int* b) 
{ 
	int temp = *a; 
	*a = *b; 
	*b = temp; 
} 

/* This function takes last element as pivot, places the pivot element at its correct position in sorted array, and places 
all smaller (smaller than pivot) to left of pivot and all greater elements to right of pivot */

int partition(int arr[], int l, int h) 
{ 
	int x = arr[h]; 
	int i = (l - 1); 

	for (int j = l; j <= h - 1; j++) { 
		if (arr[j] <= x) { 
			i++; 
			swap(&arr[i], &arr[j]); 
		} 
	} 
	swap(&arr[i + 1], &arr[h]); 
	return (i + 1); 
} 


void quickSort(int A[], int start, int end) 
{ 
	if (start < end) { 
		/* Partitioning index */
		int p = partition(A, start, end); 
		quickSort(A, start, p - 1); 
		quickSort(A, p + 1, end); 
	} 
} 


int main() 
{ 

	int n = 5; 
	int arr[n] = { 4, 2, 6, 9, 2 }; 

	quickSort(arr, 0, n - 1); 

	for (int i = 0; i < n; i++) { 
		cout << arr[i] << " "; 
	} 

	return 0; 
}