# Create variables representing from index and to index for each move
fromIndex = mdl.integer_var_list(NB_MOVES, 0, SIZE - 1, "From_")
toIndex = mdl.integer_var_list(NB_MOVES, 0, SIZE - 1, "To_")
# Add constraints between each state
for m in range(NB_MOVES):
fvar = fromIndex[m]
tvar = toIndex[m]
fromState = states[m]
toState = states[m + 1]
# Constrain location of holes
mdl.add(mdl.element(fromState, tvar) == HOLE)
# Constrain move size and direction
delta = tvar - fvar
mdl.add(mdl.allowed_assignments(delta, [-2, -1, 1, 2]))
peg = mdl.element(fromState, fvar)
mdl.add( ((peg == RED) & (delta > 0)) | ((peg == BLUE) & (delta < 0)) )
# Make moves
mdl.add(mdl.element(toState, tvar) == mdl.element(fromState, fvar))
mdl.add(mdl.element(toState, fvar) == HOLE)
# Force equality of other positions
for p in range(SIZE):
mdl.add(mdl.if_then((p != fvar) & (p != tvar), fromState[p] == toState[p]))
# Set initial position
for p in range(NB_PEGS):
mdl.add(states[0][p] == RED)
mdl.add(states[0][p + NB_PEGS + 1] == BLUE)
mdl.add(states[0][NB_PEGS] == HOLE)
where = mdl.integer_var_list(nbOrders, 0, maxDeliveries - 1, "where")
# Load of a truck
load = mdl.integer_var_list(maxDeliveries, 0, maxLoad, "load")
# Number of deliveries that are required
nbDeliveries = mdl.integer_var(0, maxDeliveries)
# Identification of which customer is assigned to a delivery
customerOfDelivery = mdl.integer_var_list(maxDeliveries, 0, nbCustomers,
"customerOfTruck")
# Transition cost for each delivery
transitionCost = mdl.integer_var_list(maxDeliveries - 1, 0, 1000,
"transitionCost")
# transitionCost[i] = transition cost between configurations i and i+1
for i in range(1, maxDeliveries):
auxVars = (truckConfigs[i - 1], truckConfigs[i], transitionCost[i - 1])
mdl.add(mdl.allowed_assignments(auxVars, CONFIGURATION_TRANSITION_COST))
# Constrain the volume of the orders in each truck
mdl.add(mdl.pack(load, where, volumes, nbDeliveries))
for i in range(0, maxDeliveries):
mdl.add(load[i] <= mdl.element(truckConfigs[i], maxTruckConfigLoad))
# Compatibility between the product type of an order and the configuration of its truck
for j in range(0, nbOrders):
configOfContainer = mdl.integer_var(
ALLOWED_CONTAINER_CONFIGS[productType[j]])
mdl.add(configOfContainer == mdl.element(truckConfigs, where[j]))
# Only one customer per delivery
for j in range(0, nbOrders):
mdl.add(mdl.element(customerOfDelivery, where[j]) == CUSTOMER_ORDERS[j][0])
