import "os"
import "strings"
+var funds = flag.Int("funds", 0,
+ "Starting funds")
+
var start = flag.String("start", "",
"The planet to start at")
-var end = flag.String("end", "",
+var flight_plan_string = flag.String("flight_plan", "",
+ "Your hidey-holes for the day, comma-separated.")
+
+var end_string = flag.String("end", "",
"A comma-separated list of acceptable ending planets.")
var planet_data_file = flag.String("planet_data_file", "planet-data",
"A comma-separated list of planets to make sure to visit")
func visit() []string {
+ if *visit_string == "" {
+ return nil
+ }
return strings.Split(*visit_string, ",")
}
+func flight_plan() []string {
+ if *flight_plan_string == "" {
+ return nil
+ }
+ return strings.Split(*flight_plan_string, ",")
+}
+
+func end() map[string]bool {
+ if *end_string == "" {
+ return nil
+ }
+ m := make(map[string]bool)
+ for _, p := range strings.Split(*flight_plan_string, ",") {
+ m[p] = true
+ }
+ return m
+}
+
type Commodity struct {
BasePrice int
CanSell bool
type planet_data struct {
Commodities map[string]Commodity
Planets map[string]Planet
- pi, ci map[string]int // Generated; not read from file
+ p2i, c2i map[string]int // Generated; not read from file
+ i2p, i2c []string // Generated; not read from file
}
func ReadData() (data planet_data) {
* Note that the sizes of each dimension are data driven. Many dimensions
* collapse to one possible value (ie, disappear) if the corresponding
* feature is not enabled.
+ *
+ * The order of the dimensions in the list of constants below determines
+ * their layout in RAM. The cargo-based 'dimensions' are not completely
+ * independent -- some combinations are illegal and not used. They are
+ * handled as three dimensions rather than one for simplicity. Placing
+ * these dimensions first causes the unused cells in the table to be
+ * grouped together in large blocks. This keeps them from polluting
+ * cache lines, and if they are large enough, prevent the memory manager
+ * from allocating pages for these areas at all.
+ *
+ * If the table gets too big to fit in RAM:
+ * * Combine the Edens, Cloaks, and UnusedCargo dimensions. Of the
+ * 24 combinations, only 15 are legal: a 38% savings.
+ * * Reduce the size of the Fuel dimension to 3. We only ever look
+ * backwards 2 units, so just rotate the logical values through
+ * the same 3 physical addresses. This is good for an 82% savings.
+ * * Reduce the size of the Edens dimension from 3 to 2, for the
+ * same reasons as Fuel above. 33% savings.
+ * * Buy more ram. (Just sayin'. It's cheaper than you think.)
+ *
*/
// The official list of dimensions:
func DimensionSizes(data planet_data) []int {
eden_capacity := data.Commodities["Eden Warp Units"].Limit
+ if *start_edens > eden_capacity {
+ eden_capacity = *start_edens
+ }
cloak_capacity := bint(*cloak)
- dims := []int{
- eden_capacity + 1,
- cloak_capacity + 1,
- eden_capacity + cloak_capacity + 1,
- *fuel + 1,
- len(data.Planets),
- len(data.Commodities),
- bint(*drones > 0) + 1,
- bint(*batteries > 0) + 1,
- 1 << uint(len(visit())),
- }
- if len(dims) != NumDimensions {
- panic("Dimensionality mismatch")
+ dims := make([]int, NumDimensions)
+ dims[Edens] = eden_capacity + 1
+ dims[Cloaks] = cloak_capacity + 1
+ dims[UnusedCargo] = eden_capacity + cloak_capacity + 1
+ dims[Fuel] = *fuel + 1
+ dims[Location] = len(data.Planets)
+ dims[Hold] = len(data.Commodities) + 1
+ dims[NeedFighters] = bint(*drones > 0) + 1
+ dims[NeedShields] = bint(*batteries > 0) + 1
+ dims[Visit] = 1 << uint(len(visit()))
+
+ // Remind myself to add a line above when adding new dimensions
+ for i, dim := range dims {
+ if dim < 1 {
+ panic(i)
+ }
}
return dims
}
func StateTableSize(dims []int) int {
- sum := 0
+ product := 1
for _, size := range dims {
- sum += size
+ product *= size
}
- return sum
+ return product
}
type State struct {
- funds, from int
-}
-
-func NewStateTable(dims []int) []State {
- return make([]State, StateTableSize(dims))
+ value, from int
}
func EncodeIndex(dims, addr []int) int {
index := addr[0]
- for i := 1; i < len(dims); i++ {
+ if addr[0] > dims[0] {
+ panic(0)
+ }
+ for i := 1; i < NumDimensions; i++ {
+ if addr[i] > dims[i] {
+ panic(i)
+ }
index = index*dims[i] + addr[i]
}
return index
}
func DecodeIndex(dims []int, index int) []int {
- addr := make([]int, len(dims))
- for i := len(dims) - 1; i > 0; i-- {
+ addr := make([]int, NumDimensions)
+ for i := NumDimensions - 1; i > 0; i-- {
addr[i] = index % dims[i]
index /= dims[i]
}
return addr
}
-/* What is the value of hauling 'commodity' from 'from' to 'to'?
- * Take into account the available funds and the available cargo space. */
-func TradeValue(data planet_data,
-from, to Planet,
-commodity string,
-initial_funds, max_quantity int) int {
- if !data.Commodities[commodity].CanSell {
- return 0
+func InitializeStateTable(data planet_data, dims []int) []State {
+ table := make([]State, StateTableSize(dims))
+
+ addr := make([]int, NumDimensions)
+ addr[Fuel] = *fuel
+ addr[Edens] = *start_edens
+ addr[Location] = data.p2i[*start]
+ table[EncodeIndex(dims, addr)].value = *funds
+
+ return table
+}
+
+/* These four fill procedures fill in the cell at address addr by
+ * looking at all the possible ways to reach this cell and selecting
+ * the best one.
+ *
+ * The other obvious implementation choice is to do this the other way
+ * around -- for each cell, conditionally overwrite all the other cells
+ * that are reachable *from* the considered cell. We choose gathering
+ * reads over scattering writes to avoid having to take a bunch of locks.
+ */
+
+func UpdateCell(table []State, here, there, value_difference int) {
+ possible_value := table[there].value + value_difference
+ if table[there].value > 0 && possible_value > table[here].value {
+ table[here].value = possible_value
+ table[here].from = there
}
- from_relative_price, from_available := from.RelativePrices[commodity]
- if !from_available {
- return 0
+}
+
+func FillCellByArriving(data planet_data, dims []int, table []State, addr []int) {
+ my_index := EncodeIndex(dims, addr)
+ other := make([]int, NumDimensions)
+ copy(other, addr)
+
+ /* Travel here via a 2-fuel unit jump */
+ if addr[Fuel]+2 < dims[Fuel] {
+ other[Fuel] = addr[Fuel] + 2
+ for other[Location] = 0; other[Location] < dims[Location]; other[Location]++ {
+ if data.Planets[data.i2p[addr[Location]]].BeaconOn {
+ UpdateCell(table, my_index, EncodeIndex(dims, other), 0)
+ }
+ }
+ other[Location] = addr[Location]
+ other[Fuel] = addr[Fuel]
}
- to_relative_price, to_available := to.RelativePrices[commodity]
- if !to_available {
- return 0
+
+ /* Travel here via a hidey hole */
+ if addr[Fuel]+1 < dims[Fuel] {
+ hole_index := (dims[Fuel] - 1) - (addr[Fuel] + 1)
+ if hole_index < len(flight_plan()) && addr[Location] == data.p2i[flight_plan()[hole_index]] {
+ other[Fuel] = addr[Fuel] + 1
+ for other[Location] = 0; other[Location] < dims[Location]; other[Location]++ {
+ UpdateCell(table, my_index, EncodeIndex(dims, other), 0)
+ }
+ other[Location] = addr[Location]
+ other[Fuel] = addr[Fuel]
+ }
}
+ /* Travel here via Eden Warp Unit */
+ if addr[Edens]+1 < dims[Edens] {
+ _, available := data.Planets[data.i2p[addr[Location]]].RelativePrices["Eden Warp Units"]
+ if !available {
+ other[Edens] = addr[Edens] + 1
+ for other[Location] = 0; other[Location] < dims[Location]; other[Location]++ {
+ UpdateCell(table, my_index, EncodeIndex(dims, other), 0)
+ }
+ other[Location] = addr[Location]
+ other[Edens] = addr[Edens]
+ }
+ }
+}
+
+func FillCellBySelling(data planet_data, dims []int, table []State, addr []int) {
+ if addr[Hold] > 0 {
+ // Can't sell and still have cargo
+ return
+ }
+ if addr[UnusedCargo] > 0 {
+ // Can't sell everything and still have 'unused' holds
+ return
+ }
+ my_index := EncodeIndex(dims, addr)
+ other := make([]int, NumDimensions)
+ copy(other, addr)
+ planet := data.i2p[addr[Location]]
+ for other[Hold] = 0; other[Hold] < dims[Hold]; other[Hold]++ {
+ commodity := data.i2c[other[Hold]]
+ if !data.Commodities[commodity].CanSell {
+ // TODO: Dump cargo
+ continue
+ }
+ relative_price, available := data.Planets[planet].RelativePrices[commodity]
+ if !available {
+ continue
+ }
+ base_price := data.Commodities[commodity].BasePrice
+ absolute_price := float64(base_price) * float64(relative_price) / 100.0
+ sell_price := int(absolute_price * 0.9)
+
+ for other[UnusedCargo] = 0; other[UnusedCargo] < dims[UnusedCargo]; other[UnusedCargo]++ {
+
+ quantity := *hold - (other[UnusedCargo] + other[Cloaks] + other[Edens])
+ sale_value := quantity * sell_price
+ UpdateCell(table, my_index, EncodeIndex(dims, other), sale_value)
+ }
+ }
+ other[UnusedCargo] = addr[UnusedCargo]
+}
+
+func FillCellByBuying(data planet_data, dims []int, table []State, addr []int) {
+ if addr[Hold] == 0 {
+ // Can't buy and then have nothing
+ return
+ }
+ my_index := EncodeIndex(dims, addr)
+ other := make([]int, NumDimensions)
+ copy(other, addr)
+ planet := data.i2p[addr[Location]]
+ commodity := data.i2c[addr[Hold]]
+ if !data.Commodities[commodity].CanSell {
+ return
+ }
+ relative_price, available := data.Planets[planet].RelativePrices[commodity]
+ if !available {
+ return
+ }
base_price := data.Commodities[commodity].BasePrice
- from_absolute_price := from_relative_price * base_price
- to_absolute_price := to_relative_price * base_price
- buy_price := from_absolute_price
- sell_price := int(float64(to_absolute_price) * 0.9)
- var can_afford int = initial_funds / buy_price
- quantity := can_afford
- if quantity > max_quantity {
- quantity = max_quantity
- }
- return (sell_price - buy_price) * max_quantity
+ absolute_price := int(float64(base_price) * float64(relative_price) / 100.0)
+ quantity := *hold - (addr[UnusedCargo] + addr[Cloaks] + addr[Edens])
+ total_price := quantity * absolute_price
+ other[Hold] = 0
+ other[UnusedCargo] = 0
+ UpdateCell(table, my_index, EncodeIndex(dims, other), -total_price)
+ other[UnusedCargo] = addr[UnusedCargo]
+ other[Hold] = addr[Hold]
}
-func FindBestTrades(data planet_data) [][]string {
- // TODO: We can't cache this because this can change based on available funds.
- best := make([][]string, len(data.Planets))
- for from := range data.Planets {
- best[data.pi[from]] = make([]string, len(data.Planets))
- for to := range data.Planets {
- best_gain := 0
- price_list := data.Planets[from].RelativePrices
- if len(data.Planets[to].RelativePrices) < len(data.Planets[from].RelativePrices) {
- price_list = data.Planets[to].RelativePrices
+func FillCellByMisc(data planet_data, dims []int, table []State, addr []int) {
+ my_index := EncodeIndex(dims, addr)
+ other := make([]int, NumDimensions)
+ copy(other, addr)
+ /* Buy Eden warp units */
+ /* Buy a Device of Cloaking */
+ if addr[Cloaks] == 1 && addr[UnusedCargo] < dims[UnusedCargo]-1 {
+ relative_price, available := data.Planets[data.i2p[addr[Location]]].RelativePrices["Device Of Cloakings"]
+ if available {
+ absolute_price := int(float64(data.Commodities["Device Of Cloakings"].BasePrice) * float64(relative_price) / 100.0)
+ other[Cloaks] = 0
+ if other[Hold] != 0 {
+ other[UnusedCargo] = addr[UnusedCargo] + 1
}
- for commodity := range price_list {
- gain := TradeValue(data,
- data.Planets[from],
- data.Planets[to],
- commodity,
- 10000000,
- 1)
- if gain > best_gain {
- best[data.pi[from]][data.pi[to]] = commodity
- gain = best_gain
+ UpdateCell(table, my_index, EncodeIndex(dims, other), -absolute_price)
+ other[UnusedCargo] = addr[UnusedCargo]
+ other[Cloaks] = addr[Cloaks]
+ }
+ }
+ /* Silly: Dump a Device of Cloaking */
+ /* Buy Fighter Drones */
+ /* Buy Shield Batteries */
+ /* Visit this planet */
+}
+
+func FillStateTable2Iteration(data planet_data, dims []int, table []State,
+addr []int, f func(planet_data, []int, []State, []int)) {
+ /* TODO: Justify the safety of the combination of this dimension
+ * iteration and the various phases f. */
+ for addr[Hold] = 0; addr[Hold] < dims[Hold]; addr[Hold]++ {
+ for addr[Cloaks] = 0; addr[Cloaks] < dims[Cloaks]; addr[Cloaks]++ {
+ for addr[UnusedCargo] = 0; addr[UnusedCargo] < dims[UnusedCargo]; addr[UnusedCargo]++ {
+ for addr[NeedFighters] = 0; addr[NeedFighters] < dims[NeedFighters]; addr[NeedFighters]++ {
+ for addr[NeedShields] = 0; addr[NeedShields] < dims[NeedShields]; addr[NeedShields]++ {
+ for addr[Visit] = 0; addr[Visit] < dims[Visit]; addr[Visit]++ {
+ f(data, dims, table, addr)
+ }
+ }
}
}
}
}
- return best
+}
+
+func FillStateTable2(data planet_data, dims []int, table []State,
+fuel_remaining, edens_remaining int, planet string, barrier chan<- bool) {
+ addr := make([]int, len(dims))
+ addr[Edens] = edens_remaining
+ addr[Fuel] = fuel_remaining
+ addr[Location] = data.p2i[planet]
+ FillStateTable2Iteration(data, dims, table, addr, FillCellByArriving)
+ FillStateTable2Iteration(data, dims, table, addr, FillCellBySelling)
+ FillStateTable2Iteration(data, dims, table, addr, FillCellByBuying)
+ FillStateTable2Iteration(data, dims, table, addr, FillCellByMisc)
+ barrier <- true
+}
+
+/* Filling the state table is a set of nested for loops NumDimensions deep.
+ * We split this into two procedures: 1 and 2. #1 is the outer, slowest-
+ * changing indexes. #1 fires off many calls to #2 that run in parallel.
+ * The order of the nesting of the dimensions, the order of iteration within
+ * each dimension, and where the 1 / 2 split is placed are carefully chosen
+ * to make this arrangement safe.
+ *
+ * Outermost two layers: Go from high-energy states (lots of fuel, edens) to
+ * low-energy state. These must be processed sequentially and in this order
+ * because you travel through high-energy states to get to the low-energy
+ * states.
+ *
+ * Third layer: Planet. This is a good layer to parallelize on. There's
+ * high enough cardinality that we don't have to mess with parallelizing
+ * multiple layers for good utilization (on 2011 machines). Each thread
+ * works on one planet's states and need not synchronize with peer threads.
+ */
+func FillStateTable1(data planet_data, dims []int, table []State) {
+ barrier := make(chan bool, len(data.Planets))
+ eden_capacity := data.Commodities["Eden Warp Units"].Limit
+ work_units := (float64(*fuel) + 1) * (float64(eden_capacity) + 1)
+ work_done := 0.0
+ for fuel_remaining := *fuel; fuel_remaining >= 0; fuel_remaining-- {
+ for edens_remaining := eden_capacity; edens_remaining >= 0; edens_remaining-- {
+ for planet := range data.Planets {
+ go FillStateTable2(data, dims, table, fuel_remaining,
+ edens_remaining, planet, barrier)
+ }
+ for _ = range data.Planets {
+ <-barrier
+ }
+ work_done++
+ print(fmt.Sprintf("\r%3.0f%%", 100*work_done/work_units))
+ }
+ }
+ print("\n")
+}
+
+func FindBestState(data planet_data, dims []int, table []State) int {
+ addr := make([]int, NumDimensions)
+ addr[Edens] = *end_edens
+ addr[Cloaks] = dims[Cloaks] - 1
+ addr[NeedFighters] = dims[NeedFighters] - 1
+ addr[NeedShields] = dims[NeedShields] - 1
+ addr[Visit] = dims[Visit] - 1
+ // Fuel, Hold, UnusedCargo left at 0
+ max_index := -1
+ max_value := 0
+ for addr[Location] = 0; addr[Location] < dims[Location]; addr[Location]++ {
+ index := EncodeIndex(dims, addr)
+ if table[index].value > max_value {
+ max_value = table[index].value
+ max_index = index
+ }
+ }
+ return max_index
+}
+
+func Commas(n int) (s string) {
+ r := n % 1000
+ n /= 1000
+ for n > 0 {
+ s = fmt.Sprintf(",%03d", r) + s
+ r = n % 1000
+ n /= 1000
+ }
+ s = fmt.Sprint(r) + s
+ return
+}
+
+func DescribePath(data planet_data, dims []int, table []State, start int) (description []string) {
+ for index := start; index > 0 && table[index].from > 0; index = table[index].from {
+ line := fmt.Sprintf("%13v", Commas(table[index].value))
+ addr := DecodeIndex(dims, index)
+ prev := DecodeIndex(dims, table[index].from)
+ if addr[Location] != prev[Location] {
+ from := data.i2p[prev[Location]]
+ to := data.i2p[addr[Location]]
+ if addr[Fuel] != prev[Fuel] {
+ line += fmt.Sprintf(" Jump from %v to %v (%v reactor units)", from, to, prev[Fuel]-addr[Fuel])
+ } else if addr[Edens] != prev[Edens] {
+ line += fmt.Sprintf(" Eden warp from %v to %v", from, to)
+ } else {
+ panic("Traveling without fuel?")
+ }
+ }
+ if addr[Hold] != prev[Hold] {
+ if addr[Hold] == 0 {
+ quantity := *hold - (prev[UnusedCargo] + prev[Edens] + prev[Cloaks])
+ line += fmt.Sprintf(" Sell %v %v", quantity, data.i2c[prev[Hold]])
+ } else if prev[Hold] == 0 {
+ quantity := *hold - (addr[UnusedCargo] + addr[Edens] + addr[Cloaks])
+ line += fmt.Sprintf(" Buy %v %v", quantity, data.i2c[addr[Hold]])
+ } else {
+ panic("Switched cargo?")
+ }
+
+ }
+ if addr[Cloaks] == 1 && prev[Cloaks] == 0 {
+ // TODO: Dump cloaks, convert from cargo?
+ line += " Buy a Cloak"
+ }
+ description = append(description, line)
+ }
+ return
}
// (Example of a use case for generics in Go)
-func IndexPlanets(m *map[string]Planet) map[string]int {
- index := make(map[string]int, len(*m))
- i := 0
+func IndexPlanets(m *map[string]Planet, start_at int) (map[string]int, []string) {
+ e2i := make(map[string]int, len(*m)+start_at)
+ i2e := make([]string, len(*m)+start_at)
+ i := start_at
for e := range *m {
- index[e] = i
+ e2i[e] = i
+ i2e[i] = e
i++
}
- return index
+ return e2i, i2e
}
-func IndexCommodities(m *map[string]Commodity) map[string]int {
- index := make(map[string]int, len(*m))
- i := 0
+func IndexCommodities(m *map[string]Commodity, start_at int) (map[string]int, []string) {
+ e2i := make(map[string]int, len(*m)+start_at)
+ i2e := make([]string, len(*m)+start_at)
+ i := start_at
for e := range *m {
- index[e] = i
+ e2i[e] = i
+ i2e[i] = e
i++
}
- return index
+ return e2i, i2e
}
func main() {
flag.Parse()
data := ReadData()
- data.pi = IndexPlanets(&data.Planets)
- data.ci = IndexCommodities(&data.Commodities)
+ data.p2i, data.i2p = IndexPlanets(&data.Planets, 0)
+ data.c2i, data.i2c = IndexCommodities(&data.Commodities, 1)
dims := DimensionSizes(data)
- table := NewStateTable(dims)
- table[0] = State{1, 1}
- best_trades := FindBestTrades(data)
-
- for from := range data.Planets {
- for to := range data.Planets {
- best_trade := "(nothing)"
- if best_trades[data.pi[from]][data.pi[to]] != "" {
- best_trade = best_trades[data.pi[from]][data.pi[to]]
- }
- fmt.Printf("%s to %s: %s\n", from, to, best_trade)
+ table := InitializeStateTable(data, dims)
+ FillStateTable1(data, dims, table)
+ best := FindBestState(data, dims, table)
+ if best == -1 {
+ print("Cannot acheive success criteria\n")
+ } else {
+ description := DescribePath(data, dims, table, best)
+ for i := len(description) - 1; i >= 0; i-- {
+ fmt.Println(description[i])
}
}
}
projects / planeteer / blobdiff