I'm having trouble getting the switch to constantly loop until user tells the program to stop. When the user is prompt to put in a N to loop, they should be sent back to the top of the switch

        char stop;
    while(stop == 'N'){
        switch(choice){
            case 1:
                System.out.println("Enter the time in seconds:");
                time = input.nextInt();
                displacement = (Math.pow(time,4)) + 16;
                System.out.println("Felix's displacement is equal to " + displacement + " meters");
                System.out.println("Stop the application(Y/N)");
                stop = input.findWithinHorizon(".",0).charAt(0);
                break;
            case 2:
                System.out.println("Enter the time in seconds:");
                time = input.nextInt();
                velocity = 4*(Math.pow(time,3));
                System.out.println("Felix's velocity is equal to " + velocity + " m/s");
                break;
            case 3:
                System.out.println("Enter the time in seconds:");
                time = input.nextInt();
                acceleration = 12*(Math.pow(time,2));
                System.out.println("Felix's acceleration is equal to " + acceleration + " m/(s*s)");
                break;
            default:
                System.out.println("Please select a choice");

        }
    }
}

1. Crudely: initialise stop on declaration:

char stop = 'N';

1. Better: replace your while with a do while loop:

   do {

   } while (stop == 'N')

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