Coloring of graph

 from random import randint

#todo

#chromatic number

#currently supporting in max 4 color graph

n=input("Enter Your vertex seprated by space:").split()

vac={}

for vertex in n:

c=input(f"{vertex} is connected to? give value seprated by space:")

vac[vertex]=c.split()

CV=[]

CG={}

first=True

for vertex in n:

colors=["RED","GREEN","BLUE","YELLOW"]

if first==True:

first=False

RC=colors[randint(0,len(colors)-1)]

CG[vertex]=RC

CV.append(vertex)

continue

temp2=vac[vertex]

for conn in temp2:

if conn in CG:

CP=CG[conn]

CI=colors.index(CP)

colors.pop(CI)

CG[vertex]=colors[randint(0,len(colors)-1)]

CV.append(vertex)

print(CG)