why dont you use endl; when printing strings?

Question

string a = "whats up";

cout << a;

return 0;

Answer 1

you can

you do not with cin..

cout << "hi" << endl; // ok
cin >> a << endl // not ok

you example goes

string a = "whats up";
cout << a << endl;

Answer 2

generally we can use but in your context I think when we use endl it remove everything in buffer which take some time..so, in order to be reduce time complexity we don't use.But using endl is good practice..

Answer 3

Because it only prints one string and it's unneccessary (unless you use system("exit"); ).