def generate_solution(pizza):
# Create new solution
solution = Solution(pizza)
# copy all the part to create a random order
slices = deepcopy(slices_module.slices)
shuffle(slices)
# Add all the possible slices following the slices order
for slice in slices:
solution.add_slice(slice)
return solution
def generate_solution (prev_sol, hole=None):
# Create new solution
solution = Solution(prev_sol.pizza, prev_sol.slices.values())
# look for possible slices
possible_slices = {}
possible_slices_per_tile = {}
# enumerate all the tiles
possible_idxs = []
if hole == None:
for i, row in enumerate(prev_sol.coverage):
for j, val in enumerate(row):
if val == -1:
possible_idxs += slices_module.slices_per_tile[i][j]
else:
for i in range(hole[0], hole[2]):
for j in range(hole[1], hole[3]):
possible_idxs += slices_module.slices_per_tile[i][j]
# extract uniq idxs
uniq = set(possible_idxs)
# Look for possible tiles
for idx in uniq:
possible = True
slice = slices_module.slices[idx]
for i in range(slice[0], slice[2]+1):
for j in range(slice[1], slice[3]+1):
if prev_sol.coverage[i][j] != -1:
possible = False
if possible:
#save slice
possible_slices[idx] = slice
# prepare the constraints
for r in range(slice[0], slice[2]+1):
# Init row
if not r in possible_slices_per_tile:
possible_slices_per_tile[r] = {}
# fill row
for c in range(slice[1], slice[3]+1):
# Init col
if not c in possible_slices_per_tile[r]:
possible_slices_per_tile[r][c] = []
# fill col
possible_slices_per_tile[r][c].append(idx)
# If no slice can be put on
if len(possible_slices) == 0:
return prev_sol
# Create MIP model
m = Model("mip")
# m.setParam( 'OutputFlag', False )
vars = {}
sizes = {}
# Add all the possible slices to the model
for idx in possible_slices:
slice = possible_slices[idx]
vars[idx] = m.addVar(vtype=GRB.BINARY, name="{}".format(idx))
sizes[idx] = (slice[2]+1 - slice[0]) * (slice[3]+1 - slice[1])
# Create the maximization objective
m.setObjective(quicksum([vars[idx] * sizes[idx] for idx in vars]), GRB.MAXIMIZE)
# Add one constraint per tile
constraint_id = 0
for row_idx in possible_slices_per_tile:
for col_idx in possible_slices_per_tile[row_idx]:
sl_list = possible_slices_per_tile[row_idx][col_idx]
# no slice on the tile
if len(sl_list) == 0:
continue
# add a constraint on the tile
m.addConstr(quicksum([vars[idx] for idx in sl_list]) <= 1, "c{}".format(constraint_id))
constraint_id += 1
m.optimize()
for v in m.getVars():
# print(v.varName, v.x)
if v.x == 1:
solution.add_slice(possible_slices[int(v.varName)])
return solution
