I would actually recommend not doing that... sure it's easy, but using the using namespace std; line should probably not outlive your early-to-mid learning stages... it'd be better to put
Code:
using std::cout;
using std::endl;
that way you'll know what exactly comes from the standard library. for examle, I'll bet you'd never know why this code is wrong just by looking at it:
Code:
#include<iostream>
int main()
{
std::cout<<"Hello World"<<std::endl;
ifstream file("file.txt"); //open a file
file.close(); //close the file
return 0; //return 0 to the OS
}