package sorting;

public class MergeSort {

void merge(int arr[], int beg, int mid, int end) {

int l = mid - beg + 1;

int r = end - mid;

int LeftArray[] = new int[l];

int RightArray[] = new int[r];

for (int i = 0; i < l; ++i)

LeftArray[i] = arr[beg + i];

for (int j = 0; j < r; ++j)

RightArray[j] = arr[mid + 1 + j];

int i = 0, j = 0;

int k = beg;

while (i < l && j < r) {

if (LeftArray[i] <= RightArray[j]) {

arr[k] = LeftArray[i];

i++;

} else {

arr[k] = RightArray[j];

j++;

}

k++;

}

while (i < l) {

arr[k] = LeftArray[i];

i++;

k++;

}

while (j < r) {

arr[k] = RightArray[j];

j++;

k++;

}

}

void sort(int arr[], int beg, int end) {

if (beg < end) {

int mid = (beg + end) / 2;

sort(arr, beg, mid);

sort(arr, mid + 1, end);

merge(arr, beg, mid, end);

}

}

public static void main(String args[]) {

int arr[] = { 90, 23, 101, 45, 65, 23, 67, 89, 34, 23 };

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

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

System.out.print(arr[i] + " ");

}

MergeSort ob = new MergeSort();

ob.sort(arr, 0, arr.length - 1);

System.out.println("\n\nSorted array");

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

System.out.print(arr[i] + " ");

}

}

}