Dynamic 2d Array In C++

#include <iostream>
using namespace std;

int main() {

int row,col;
int **ptr;

cout<<"enter Rows : ";
cin>>row;
cout<<"enter Cols : ";
cin>>col;
ptr= new int*[row];

for (int i=0;i<row;i++)  // 2d array dynamically
 {
  ptr[i]= new int[col];
 }

for (int i=0;i<row;i++)  // delete 2d array
 {
 delete [] ptr[i];
 }
delete [] ptr;

system("pause");
return 0;
}