Renames the vertices of a graph, in its vertex list and in every edge.
VertexReplace[g, {v1 -> w1, v2 -> w2, …}]
VertexReplace[{v -> w, …}, …]
VertexList[VertexReplace[Graph[{1 <-> 2}], 1 -> 5]]
→ {5, 2}ToString[EdgeList[VertexReplace[Graph[{1 -> 2}], 2 -> y]], InputForm]
→ {DirectedEdge[1, y]}VertexList[VertexReplace[Graph[{1 <-> 2, 2 <-> 3}], {1 -> 3}]]
→ {3, 2}