@Override
	public double reValue(double x, double y) {

		if (g == 0) {
			value = x;
			word = "x";
		} else if (g == 1) {
			value = y;
			word = "y";
		} else if (g == 2) {
			value = y + x;
			word = "y+x";
		} else if (g == 3) {
			value = y * x;
			word = "y*x";
		}
		return value;
	}