用构造的方法给出了I(∧Cn,4),I(Fn,4)和Pn,4的优美标号,证明了I(∧Cn,4),I(Fn,4)和Pn,4都是优美图.
The constructor method gives graceful labeling of I(∧Cn,4),I(Fn,4)and Pn,4,thus proved that I(∧Cn,4),I(Fn,4)and Pn,4are graceful graphs.