Question: I can make a camera which will open after get any message and replay this image by photo in an Android phone. How can I make it without using user permission?

```java
 Intent in = new Intent(
                    android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            in.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            context.startActivity(in);

```

Answer: 
cout and cin are object in std namespace. So there are two solution use namespace:

```
#include <stdafx.h>
#include <iostream>
using namespace std;

```

Or explicitly write it:

```
int main()
{
    std::cout << "Please enter a number: ";
    int x;
    std::cin >> x;
    std::cout << "Your multiplied x2 number is: "<<doubleNumber(x);
    return 0;
}

```
Use either of the following:-

```
#include <iostream>
using namespace std;

```

OR

```
std::cout and std::cin.

```

Although latter is preferred over former.