A bipartite graph always contain cycles of

A bipartite graph always contains cycles of even length. This is because in a bipartite graph, the vertices can be divided into two disjoint sets such that every edge connects a vertex in one set to a vertex in the other set. Starting from any vertex, every move to a vertex in the other set increases the length of the path by 1. Therefore, to return to the original vertex and form a cycle, the path must have an even length.