public class MergeSort {
private int[] array;
private int[] tempMergArr;
private int length;
public static void
main(String a[]) {
int[] inputArr
= { 2, 5, 2, 8, 5, 6, 8, 8 };
MergeSort mms = new MergeSort();
mms.sort(inputArr);
System.out.println("Sorted lis is ::");
for (int i : inputArr) {
System.out.print(i);
System.out.print(" ");
}
}
public void
sort(int inputArr[]) {
this.array = inputArr;
this.length = inputArr.length;
this.tempMergArr
= new int[length];
doMergeSort(0,
length - 1);
}
private void
doMergeSort(int lowerIndex, int higherIndex) {
if (lowerIndex
< higherIndex) {
int middle = lowerIndex
+ (higherIndex - lowerIndex) / 2;
// Below step sorts the left side of the array
doMergeSort(lowerIndex,
middle);
// Below step sorts the right side of the array
doMergeSort(middle + 1, higherIndex);
// Now merge both sides
mergeParts(lowerIndex,
middle, higherIndex);
}
}
private void
mergeParts(int lowerIndex, int middle, int higherIndex) {
for (int i = lowerIndex; i <= higherIndex;
i++) {
tempMergArr[i] = array[i];
}
int i = lowerIndex;
int j = middle + 1;
int k = lowerIndex;
while
(i <= middle && j <= higherIndex) {
if (tempMergArr[i] <= tempMergArr[j]) {
array[k] = tempMergArr[i];
i++;
}
else {
array[k] = tempMergArr[j];
j++;
}
k++;
}
while
(i <= middle) {
array[k] = tempMergArr[i];
k++;
i++;
}
}
}
Output:
Sorted list is ::
2 2 5 5 6 8 8 8
