Control Stick Doesn't Work?

I have two Nintendo GameCube controllers, and I used them to play Super Smash Bros. for Wii U. They are not the new kinds of GC Controllers with the smash logo, they're just the good ol' normal ones from when the original gamecube came out.

Anyways, one of my controllers c-stick went completely off, and it doesn't input anything anymore. The c-stick inputted attacks on my control scheme, so I switched to my other controller.

Then soon afterwards, the OTHER joystick didn't work, which was the larger gray one that detected movement.

The Nintendo GameCube controller is my primary choice of controller at tournaments, so if anybody has had issues regarding this, any answers will be very much appreciated.