del_vertices(+Graph,
+Vertices, -NewGraph)
?- del_vertices([2,1],
[1-[3,5],2-[4],3-[],4-[5],
5-[],6-[],7-[2,6],8-[]],
NL).
NL = [3-[],4-[5],5-[],6-[],7-[6],8-[]]
del_vertices(+Graph,
+Vertices, -NewGraph)
?- del_vertices([2,1],
[1-[3,5],2-[4],3-[],4-[5],
5-[],6-[],7-[2,6],8-[]],
NL).
NL = [3-[],4-[5],5-[],6-[],7-[6],8-[]]