ArrayRotationByRecursion.cpp

/*
Array = {1 2 3 4 5 6} d=3
First reverse (0,d-1) = {3 2 1} Second reverse (d,n-1) = {6 5 4}
Whole  reverse(0,n-1) = {4 5 6 1 2 3}*/

#include <iostream>
using namespace std;
int arr_n;

void arrayReverse(int local_arr[], int start, int end)
{
	int temp;
	while (start < end)
	{
		temp = local_arr[start];
		local_arr[start] = local_arr[end];
		local_arr[end] = temp;
		++start;
		--end;
	}
}
void rotateArrayLeft(int local_arr[], int d)
{

	arrayReverse(local_arr, 0, d - 1);
	/*cout<<"\nLocal Array after 1 Rotation is :";
		for(int i=0;i<arr_n;i++)
			cout<<local_arr[i]<<" ";
		*/
	arrayReverse(local_arr, d, arr_n - 1);
	/*cout<<"\nLocal Array after 2 Rotation is :";
		for(int i=0;i<arr_n;i++)
			cout<<local_arr[i]<<" ";*/

	arrayReverse(local_arr, 0, arr_n - 1);
	/*cout<<"\nLocal Array after 3rd Rotation is :";
		for(int i=0;i<arr_n;i++)
			cout<<local_arr[i]<<" ";*/
}
int main()
{
	int arr[50], d;
	cout << "Number of values in array:";
	cin >> arr_n;
	cout << "\nEnter " << arr_n << " values :";
	for (int i = 0; i < arr_n; i++)
		arr[i] = 0;
	for (int i = 0; i < arr_n; i++)
		cin >> arr[i];

	cout << "\nNumber elements wants rotate:";
	cin >> d;

	rotateArrayLeft(arr, d);
	cout << "\nArray after Rotation is :";
	for (int i = 0; i < arr_n; i++)
		cout << arr[i] << " ";
	return 0;
}