In this paper,we set the conception of quadratic form of a graph and quartic form of a graph, the necessary sufficient condition on 1-factor of graphs and 2-factor of paar graphs and obtain a counting formula for 1-factor of graphs.
本文应用图的二次型与四次型的概念，得到图有１－因子、偶图有２－因子的充要条件，并且得到了图的１－因子的计数公式。
