BINARY VERSION
Union graph:
directed: true
vcount: 5
edges: {
0 1
1 2
2 2
2 3
2 4
}
Edge maps:
( 0 1 2 3 )
( 0 1 2 4 )


N-ARY VERSION

Empty graph list:
Union graph:
directed: true
vcount: 0
edges: {
}
Edge maps:
{
}

Non-empty directed graph list 1:
Union graph:
directed: true
vcount: 2
edges: {
1 0
0 1
}
Edge maps:
{
  0: ( 1 0 )
  1: ( 1 0 )
  2: ( 1 0 )
  3: ( 1 0 )
  4: ( 1 0 )
  5: ( 1 0 )
  6: ( 1 0 )
  7: ( 1 0 )
  8: ( 1 0 )
  9: ( 1 0 )
}

Non-empty directed graph list 2:
0 1
1 0
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
Union graph:
directed: true
vcount: 11
edges: {
9 10
8 9
7 8
6 7
5 6
4 5
3 4
2 3
1 2
1 0
0 1
}
Edge maps:
{
  0: ( 10 9 )
  1: ( 8 9 )
  2: ( 7 9 )
  3: ( 6 9 )
  4: ( 5 9 )
  5: ( 4 9 )
  6: ( 3 9 )
  7: ( 2 9 )
  8: ( 1 9 )
  9: ( 0 9 )
}

Undirected graph list:
0 1
0 1
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
Union graph:
directed: false
vcount: 11
edges: {
10 9
9 8
8 7
7 6
6 5
5 4
4 3
3 2
2 1
1 0
1 0
}
Edge maps:
{
  0: ( 10 9 )
  1: ( 8 9 )
  2: ( 7 9 )
  3: ( 6 9 )
  4: ( 5 9 )
  5: ( 4 9 )
  6: ( 3 9 )
  7: ( 2 9 )
  8: ( 1 9 )
  9: ( 0 9 )
}