public class Test {
    public static void main(String[] args) {
        ElectricInverter inverter = new ElectricInverter();
        int AC = 220;
        System.out.println(inverter.invert(AC));
    }
}

class ElectricInverter {    
    public static final int AC = ~220;
    public static final int DC = -110;
    public static final int GROUND = 0;
    
    int invert(int type) {
        if (type == AC) {
            return DC;
        }
        else if (type == DC) {
            return AC;
        }
        return GROUND;
    }
}