My if statement prints on every if statement in my while loop regardless if it is false

So i'm making a text adventure game i'm just programming directions. I have a script with north south etc. And then an if statement that says if the user enters something other than a direction it will say that is not a direction and loop to the top but its not working. It will always print That is not a direction even if I enter the right input. Can anyone help?

#include <iomanip>
#include <string>
#include <iostream>
using namespace std;



int main()
{
    string input;
    while (input != "north", "n", "south", "s", "east", "e") {
        cout << "Enter a direction" << endl;
        getline(cin, input);
        if (input == "north" || input == "n") {
            cout << "north" << endl;
        }
        if (input == "west" || input == "w") {
            cout << "west" << endl;
        }
        if (input == "east" || input == "e") {
            cout << "east" << endl;
        }
        if (input == "south" || input == "s") {
            cout << "south" << endl;
        }
        if (input != "n", "s", "e", "w")
        {
            cout << "That is not a direction" << endl;
        }
    }
    return 0;
}