∫ The two endpoints of each line segment in the figure are painted with different colors.

It can be classified according to the kind of painted color,

If four colors are used for B, D, E and F, there are 44× 1× 1=24 coloring methods;

If three colors are used for B, D, E and F, there are 43× 2× 2+A43× 2×1× 2 =192 coloring methods.

If B, D, E and F are two colors, there are 42×2×2=48 coloring methods;

According to the principle of classified counting, there are 24+ 192+48=264 different coloring methods.