Block Swap Algorithm for Array Rotation

	#include <iostream>
	#include <cstdio>
	using namespace std;
	void swap(int nums[],int start,int end,int d)
	{
	for(int i=0;i<d;i++) {
	int t=nums[start+i];
	nums[start+i]=nums[end+i];
	nums[end+i]=t;
	}
	}
	void rotateLeft(int* nums, int numsSize, int k) {
	k = k%numsSize;
	if(k==0 || k==numsSize)
	return;
	if(numsSize-k==k)
	{
	swap(nums,0,k,k);
	return;
	}
	if(k<numsSize-k) {
	swap(nums,0,numsSize-k,k);
	rotateLeft(nums,numsSize-k,k);
	}
	else {
	swap(nums,0,k,numsSize-k);
	rotateLeft(nums+numsSize-k,k,2*k-numsSize);
	}
	}
	void rotateRight(int* nums, int numsSize, int k) {
	k = k%numsSize;
	if(k==0 || k==numsSize)
	return;
	if(numsSize-k==k)
	{
	swap(nums,0,k,k);
	return;
	}
	if(k<numsSize-k) {
	swap(nums,0,numsSize-k,k);
	rotateRight(nums+k,numsSize-k,k);
	}
	else {
	swap(nums,0,k,numsSize-k);
	rotateRight(nums,k,2*k-numsSize);
	}
	}
	int main() {
	int n,k;
	cin>>n>>k;
	int arr[n];
	for(int i=0;i<n;i++)
	cin>>arr[i];
	rotateLeft(arr,n,k);
	cout<<"After Left Rotation : ";
	for(int i=0;i<n;i++)
	cout<<arr[i]<<" ";
	cout<<endl;
	rotateRight(arr,n,k);
	cout<<"After Right Rotation : ";
	for(int i=0;i<n;i++)
	cout<<arr[i]<<" ";
	cout<<endl;
	}

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