Me and my group are working on a project for our engineering class using the new EV3 and I'm having trouble figuring out what to do. The problem is we're given only one color sensor and we're supposed to follow a line and complete additional tasks at the same time. The tasks include coming up to two seperate yellow lines through the black line. At the first yellow line, you're supposed to push an object, return to the line, and follow to the next yellow mark. At the second Yellow line, you are to lift up a flag and carry it. The problem we're having is incorporating a smooth line follow or even proportional line follow and trying to deal with extra colors. Can somebody please help?

Are you sure you are posting in the correct forum? My understanding is that RobotC doesn't support EV3 yet. So, it doesn't really help you if we give you example code in RobotC unless you are just seeking for advice on the algorithm. In any case, I have a hard time picturing your problem. You probably need to show us a drawing on the challenge.