2-Dimensional Array through pointer using C++

//Two Dimensional Array through Pointer in C++ 

#include<iostream>

using namespace std;

int main()

{

 int arr[2][3]={

        {10,20,30},

        {40,50,60}};

        int* ptr;

    ptr=(int*)arr;

    cout<<sizeof(int);

    cout<<endl<<"Values of the array:";

    for(int i=0;i<6;i++)

        cout<<*(ptr+i)<<" ";

    cout<<endl<<"Now Enter 5 values to array:"<<endl;

    for(int i=0;i<6;i++)

    {

        cin>>*(ptr+i);//because cin takes variable name to write not address

    }

    cout<<endl<<"Again Values of the array:";

    for(int i=0;i<6;i++)

        cout<<*(ptr+i)<<" ";

    return 0;

}//end of main