def color_freq(vertices, coloring):
res = priorityDictionary()
for v in vertices:
c = coloring[v]
if c not in res:
res[c] = 0
res[c] += 1
return res
def color_freq(vertices, coloring):
res = priorityDictionary()
for v in vertices:
c = coloring[v]
if c not in res:
res[c] = 0
res[c] += 1
return res
def color_by_ordering(graph, vchoice, cchoice, upd=None):
cols = Coloring()
n = len(graph)
usedCols = priorityDictionary()
uncolored = set(graph.nodes)
while len(uncolored) > 0:
v = vchoice(uncolored, cols, graph)
neighbourCols = {}
for w in graph.neighbours(v):
if w in cols:
if cols[w] not in neighbourCols:
neighbourCols[cols[w]] = 0
neighbourCols[cols[w]] += 1
cols[v] = cchoice(neighbourCols, usedCols)
if cols[v] not in usedCols:
usedCols[cols[v]] = 0
usedCols[cols[v]] += 1
uncolored.remove(v)
if upd:
upd(v, cols, usedCols, graph)
return cols
def color_by_ordering(graph, vchoice, cchoice, upd=None):
cols = Coloring()
n = len(graph)
usedCols = priorityDictionary()
uncolored = set(graph.nodes)
while len(uncolored) > 0:
v = vchoice(uncolored, cols, graph)
neighbourCols = {}
for w in graph.neighbours(v):
if w in cols:
if cols[w] not in neighbourCols:
neighbourCols[cols[w]] = 0
neighbourCols[cols[w]] += 1
cols[v] = cchoice(neighbourCols, usedCols)
if cols[v] not in usedCols:
usedCols[cols[v]] = 0
usedCols[cols[v]] += 1
uncolored.remove(v)
if upd:
upd(v, cols, usedCols, graph)
return cols