-- Test graph with 1 vertex --
directed: false
vcount: 0
edges: {
}

-- Test graph with 2 vertices --
directed: false
vcount: 2
edges: {
0 1
1 1
}

-- Test graph with OUT mode --
directed: true
vcount: 4
edges: {
0 1
0 2
0 3
1 2
2 3
3 1
}

-- Test graph with IN mode --
directed: true
vcount: 4
edges: {
1 0
1 2
2 0
2 3
3 0
3 1
}

-- Test graph with MUTUAL mode --
directed: true
vcount: 4
edges: {
0 1
0 2
0 3
1 0
1 2
1 3
2 0
2 1
2 3
3 0
3 1
3 2
}

-- Test graph with UNDIRECTED mode 
directed: false
vcount: 4
edges: {
0 1
0 2
0 3
1 2
1 3
2 3
}

-- Test graph with center equal to n/2 --
directed: true
vcount: 4
edges: {
0 1
1 3
2 0
2 1
2 3
3 0
}

-- Test graph with center equal to n - 1: --
directed: true
vcount: 4
edges: {
0 1
1 2
2 0
3 0
3 1
3 2
}

-- Test graph with center equal to 1: --
directed: true
vcount: 4
edges: {
0 2
1 0
1 2
1 3
2 3
3 0
}

