import "os"
import "strings"
+var funds = flag.Int("funds", 0,
+ "Starting funds")
+
var start = flag.String("start", "",
"The planet to start at")
+var flight_plan_string = flag.String("flight_plan", "",
+ "Your hidey-holes for the day, comma-separated.")
+
var end = flag.String("end", "",
"A comma-separated list of acceptable ending planets.")
"A comma-separated list of planets to make sure to visit")
func visit() []string {
+ if *visit_string == "" {
+ return []string{}
+ }
return strings.Split(*visit_string, ",")
}
+func flight_plan() []string {
+ if *flight_plan_string == "" {
+ return []string{}
+ }
+ return strings.Split(*flight_plan_string, ",")
+}
+
type Commodity struct {
BasePrice int
CanSell bool
* 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 := make([]int, NumDimensions)
dims[Edens] = eden_capacity + 1
}
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
+ 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
}
-func FillStateCell(data planet_data, dims []int, table []State, addr []int) {
+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
}
-func FillStateTable2(data planet_data, dims []int, table []State,
-fuel_remaining, edens_remaining int, planet string, barrier chan<- bool) {
- /* The dimension nesting order up to this point is important.
- * Beyond this point, it's not important.
- *
- * It is very important when iterating through the Hold dimension
- * to visit the null commodity (empty hold) first. Visiting the
- * null commodity represents selling. Visiting it first gets the
- * action order correct: arrive, sell, buy, leave. Visiting the
- * null commodity after another commodity would evaluate the action
- * sequence: arrive, buy, sell, leave. This is a useless action
- * sequence. Because we visit the null commodity first, we do not
- * consider these action sequences.
- */
- eden_capacity := data.Commodities["Eden Warp Units"].Limit
- addr := make([]int, len(dims))
- addr[Edens] = edens_remaining
- addr[Fuel] = fuel_remaining
- addr[Location] = data.p2i[planet]
+/* 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
+ }
+}
+
+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]++ {
+ UpdateCell(table, my_index, EncodeIndex(dims, other), 0)
+ }
+ other[Location] = addr[Location]
+ other[Fuel] = addr[Fuel]
+ }
+
+ /* 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()) {
+ other[Fuel] = addr[Fuel] + 1
+ other[Location] = data.p2i[flight_plan()[hole_index]]
+ UpdateCell(table, my_index, EncodeIndex(dims, other), 0)
+ other[Location] = addr[Location]
+ other[Fuel] = addr[Fuel]
+ }
+ }
+
+ /* Travel here via Eden Warp Unit */
+ for other[Edens] = addr[Edens] + 1; other[Edens] < dims[Edens]; other[Edens]++ {
+ 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] // TODO: Partial sales
+ 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
+ absolute_price := int(float64(base_price) * float64(relative_price) / 100.0)
+ quantity := *hold - addr[UnusedCargo]
+ total_price := quantity * absolute_price
+ other[Hold] = 0
+ UpdateCell(table, my_index, EncodeIndex(dims, other), -total_price)
+}
+
+func FillCellByMisc(data planet_data, dims []int, table []State, addr []int) {
+ /* Buy Eden warp units */
+ /* Buy a Device of Cloaking */
+ /* 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]++ {
- if addr[Edens] + addr[Cloaks] + addr[UnusedCargo] <=
- eden_capacity + 1 {
- 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]++ {
- FillStateCell(data, dims, table, addr)
- }
+ 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)
}
}
}
}
}
}
+}
+
+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
}
* 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) []State {
- table := make([]State, StateTableSize(dims))
+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 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)
<-barrier
}
work_done++
- fmt.Printf("\r%3.0f%%", 100 * work_done / work_units)
+ print(fmt.Sprintf("\r%3.0f%%", 100*work_done/work_units))
}
}
- return table
+ print("\n")
}
-/* 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
- }
- from_relative_price, from_available := from.RelativePrices[commodity]
- if !from_available {
- return 0
- }
- to_relative_price, to_available := to.RelativePrices[commodity]
- if !to_available {
- return 0
+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
+ var max_index int
+ 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
+}
- 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
+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
}
- return (sell_price - buy_price) * max_quantity
+ s = fmt.Sprint(r) + s
+ return
}
-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.p2i[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 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?")
}
- for commodity := range price_list {
- gain := TradeValue(data,
- data.Planets[from],
- data.Planets[to],
- commodity,
- 10000000,
- 1)
- if gain > best_gain {
- best[data.p2i[from]][data.p2i[to]] = commodity
- gain = best_gain
- }
+ }
+ 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?")
}
+
}
+ description = append(description, line)
}
- return best
+ return
}
// (Example of a use case for generics in Go)
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)
+ e2i := make(map[string]int, len(*m)+start_at)
+ i2e := make([]string, len(*m)+start_at)
i := start_at
for e := range *m {
e2i[e] = i
return e2i, i2e
}
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)
+ e2i := make(map[string]int, len(*m)+start_at)
+ i2e := make([]string, len(*m)+start_at)
i := start_at
for e := range *m {
e2i[e] = i
data.p2i, data.i2p = IndexPlanets(&data.Planets, 0)
data.c2i, data.i2c = IndexCommodities(&data.Commodities, 1)
dims := DimensionSizes(data)
- table := FillStateTable1(data, 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.p2i[from]][data.p2i[to]] != "" {
- best_trade = best_trades[data.p2i[from]][data.p2i[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)
+ fmt.Printf("Best state: %v (%v) with $%v\n",
+ best, DecodeIndex(dims, best), table[best].value)
+ description := DescribePath(data, dims, table, best)
+ for i := len(description) - 1; i >= 0; i-- {
+ fmt.Println(description[i])
}
}
projects / planeteer / blobdiff