### Question:
Difference extends InputFunction implements Serializable { @Override public double getOutput(List<Connection> inputConnections) { double output = 0d; double sum = 0d; for(Connection connection : inputConnections) { Neuron neuron = connection.getFromNeuron(); Weight weight = connection.getWeight(); double diff = neuron.getOutput() - weight.getValue(); sum += diff * diff; } output = Math.sqrt(sum); return output; }  @Override double getOutput(List<Connection> inputConnections); double[] getOutput(double[] inputs, double[] weights);  }### Answer:
@Test public void testGetOutput() { for (int i = 0; i < inputNeurons.size(); i++) { inputNeurons.get(i).setInput(inputs[i]); inputNeurons.get(i).calculate(); } double result = instance.getOutput(inputConnections); assertEquals(expected, result, 0.000001); }