graphAsMutableGraph.addNode(N1);
    assertTrue(graphAsMutableGraph.putEdge(N1, N5));
    assertTrue(graphAsMutableGraph.putEdge(N4, N1));
    assertTrue(graphAsMutableGraph.putEdge(N2, N3));
    assertThat(graph.nodes()).containsExactly(N1, N5, N4, N2, N3).inOrder();
    assertThat(graph.adjacentNodes(N1)).containsExactly(N4, N5);
    assertThat(graph.adjacentNodes(N2)).containsExactly(N3);

//
//	n0  -
//	n1  a-
//	n2  .x+
//	n3  .y+
//	n4  b-
//	n5  .cbc+
//	n6  x+
//	n7  .y+
//
// n0 is the root node, and its children are n1, n4 and n6; n1's children are
// n2 and n3; n4's child is n5; n6's child is n7. Nodes n0, n1 and n4 (marked
// with a trailing "-") are partial keys, and nodes n2, n3, n5, n6 and n7
// (marked with a trailing "+") are complete keys.
type trieNode struct {

          <y:Shape type="roundrectangle"/>
        </y:ShapeNode>
      </data>
    </node>
    <node id="n5">
      <data key="d6">
        <y:ShapeNode>
          <y:Geometry height="30.0" width="140.0" x="720.0" y="0.0"/>
          <y:Fill color="#C3D9E6" transparent="false"/>

    assertTrue(networkAsMutableNetwork.addEdge(N1, N5, E15));
    assertTrue(networkAsMutableNetwork.addEdge(N4, N1, E41));
    assertTrue(networkAsMutableNetwork.addEdge(N2, N3, E23));
    assertThat(network.nodes()).containsExactly(N1, N5, N4, N2, N3);
    assertThat(network.edges()).containsExactly(E15, E41, E23);
    assertThat(network.edgesConnecting(N1, N5)).containsExactly(E15);

          <y:Shape type="roundrectangle"/>
        </y:ShapeNode>
      </data>
    </node>
    <node id="n5">
      <data key="d6">
        <y:ShapeNode>
          <y:Geometry height="30.0" width="140.0" x="720.0" y="0.0"/>
          <y:Fill color="#C3D9E6" transparent="false"/>

            </y:ModelParameter>
          </y:NodeLabel>
          <y:Shape type="roundrectangle"/>
        </y:ShapeNode>
      </data>
    </node>
    <node id="n5">
      <data key="d5"/>
      <data key="d6">
        <y:ShapeNode>
          <y:Geometry height="30.0" width="81.0" x="470.0" y="282.5"/>
          <y:Fill color="#FF99CC" transparent="false"/>

          <y:Shape type="roundrectangle"/>
        </y:ShapeNode>
      </data>
    </node>
    <node id="n5">
      <data key="d6">
        <y:ShapeNode>
          <y:Geometry height="30.0" width="140.0" x="360.0" y="0.0"/>
          <y:Fill color="#C3D9E6" transparent="false"/>

func assemble64(n1, n2, n3, n4, n5, n6, n7, n8 byte) (dn uint64, ok bool) {
	// Check that all the digits are valid. If any of them was 0xff, their
	// bitwise OR will be 0xff.
	if n1|n2|n3|n4|n5|n6|n7|n8 == 0xff {
		return 0, false
	}
	return uint64(n1)<<58 |
			uint64(n2)<<52 |
			uint64(n3)<<46 |
			uint64(n4)<<40 |
			uint64(n5)<<34 |
			uint64(n6)<<28 |
			uint64(n7)<<22 |

   */
  MutableGraph<Integer> graphAsMutableGraph;

  static final Integer N1 = 1;
  static final Integer N2 = 2;
  static final Integer N3 = 3;
  static final Integer N4 = 4;
  static final Integer N5 = 5;
  static final Integer NODE_NOT_IN_GRAPH = 1000;

  // TODO(user): Consider separating Strings that we've defined here to capture
  // identifiable substrings of expected error messages, from Strings that we've defined

00000420  10 5e 42 1f a2 13 e5 f5  b0 cb 69 21 eb ac 6e 4d  |.^B.......i!..nM|
00000430  1d 00 94 e4 29 f1 c6 c0  0c 58 7e ca 99 e5 5d 77  |....)....X~...]w|
00000440  c3 3a 23 8e b8 a8 19 6e  35 ec e3 51 61 82 23 2f  |.:#....n5..Qa.#/|
00000450  3e af 1a e9 6b 4f 43 a9  60 d6 55 d6 75 f5 a6 84  |>...kOC.`.U.u...|
00000460  27 64 8b 0f 15 db 95 47  36 b3 14 e0 da a2 21 1e  |'d.....G6.....!.|