import static org.junit.Assert.assertEquals;
import org.junit.Test;

/**
 * Created by bing on 4/20/17.
 */
public class EuclideanTest {
    @Test
    public void evaluatesExpression() throws LengthUnmatchedException {
        DistanceFunction d = new Euclidean();
        double[] a = {0,3.0};
        double[] b = {4.0,0};
        assertEquals(5.0,d.compute(a,b),0.0001);
    }
}

@@ -373,10 +373,241 @@
 ;%0A    %7D%0A
+    @Test(expected = LengthUnmatchedException.class)%0A    public void testUnmatchedInputs()throws LengthUnmatchedException%7B%0A        double%5B%5D a = %7B1,2,3,4,5%7D;%0A        double%5B%5D b = %7B1,2,3%7D;%0A        new Euclidean().compute(a,b);%0A    %7D%0A
 %7D%0A

Add the exception test in EuclideanTest