Graph isomorphism

In graph theory, an isomorphism of graphs G and H is a bijection between the vertex sets of G and H

such that any two vertices u and v of G are adjacent in G if and only if ƒ(u) and ƒ(v) are adjacent in H. This kind of bijection is commonly described as "edge-preserving bijection", in accordance with the general notion of isomorphism being a structure-preserving bijection.