Quick sort

Iterative approach:-

public class QuickSort {

public static void main(String args[]){
int numbers[] = {-1,10,8,4,12};
int number = numbers.length;

}

private static void sort(int[] numbers,int number){
int low =0;
int i =0;
int high = number-1;
while(low<high){
int pivot = numbers[low + (high-low)/2];
 while(numbers[low]<pivot){
 low++;
 }
 while(numbers[low]>pivot){
 high--;
 }
 if(low<=high){
 exchange(low,high,numbers);
 low++;
 high--;
 }
}
if(i<high){

}


}
private static void exchange(int low, int high,int[] numbers) {
// TODO Auto-generated method stub
int temp = numbers[low];
numbers[low] = numbers[high];
numbers[high] = numbers[temp];
}
}

Recursive approach :- 

public class QuickSort {

public static void main(String[] args) {

int[] xyz = { 5, 2, 4, 8, 1, 5, 3 };

if (xyz != null && xyz.length > 0) {

quickSort(xyz, 0, xyz.length - 1);

} else {

System.out.println("Empty array");

}

printArray(xyz);

}

private static void printArray(int[] xyz) {

for (int i = 0; i < xyz.length; i++) {

System.out.println(xyz[i]);

}

}

private static void quickSort(int[] xyz, int low, int high) {

if (low < high) {

int pi = calculatePartion(xyz, low, high);

quickSort(xyz, low, pi - 1);

quickSort(xyz, pi + 1, high);

}

}

private static int calculatePartion(int[] xyz, int low, int high) {

int pivot = xyz[high];

int i = low;

for (int j = low; j < high; j++) {

if (xyz[j] <= pivot) {

swap(xyz, j, i);

i = i + 1;

}

}

swap(xyz, i, high);

return i;

}

private static void swap(int[] xyz, int i, int placeHodler) {

int temp = xyz[placeHodler];

xyz[placeHodler] = xyz[i];

xyz[i] = temp;

}

}