X-Git-Url: http://git.scottworley.com/planeteer/blobdiff_plain/5a1593ab8a31d024658664769920cbd0d5438e34..e7e4bc13603972237c4d2979a60739f0764391be:/planeteer.go diff --git a/planeteer.go b/planeteer.go index 87c7448..456e6b3 100644 --- a/planeteer.go +++ b/planeteer.go @@ -18,33 +18,64 @@ package main import "flag" +import "fmt" import "json" import "os" -import "fmt" +import "strings" + +var start = flag.String("start", "", + "The planet to start at") -var datafile = flag.String("planet_data_file", "planet-data", +var end = flag.String("end", "", + "A comma-separated list of acceptable ending planets.") + +var planet_data_file = flag.String("planet_data_file", "planet-data", "The file to read planet data from") +var fuel = flag.Int("fuel", 16, "Reactor units") + +var hold = flag.Int("hold", 300, "Size of your cargo hold") + +var start_edens = flag.Int("start_edens", 0, + "How many Eden Warp Units are you starting with?") + +var end_edens = flag.Int("end_edens", 0, + "How many Eden Warp Units would you like to keep (not use)?") + +var cloak = flag.Bool("cloak", false, + "Make sure to end with a Device of Cloaking") + +var drones = flag.Int("drones", 0, "Buy this many Fighter Drones") + +var batteries = flag.Int("batteries", 0, "Buy this many Shield Batterys") + +var visit_string = flag.String("visit", "", + "A comma-separated list of planets to make sure to visit") + +func visit() []string { + return strings.Split(*visit_string, ",") +} + type Commodity struct { - Name string BasePrice int CanSell bool Limit int } - +type Planet struct { + BeaconOn bool + /* Use relative prices rather than absolute prices because you + can get relative prices without traveling to each planet. */ + RelativePrices map[string]int +} type planet_data struct { - Commodities []Commodity - Planets []struct { - Name string - BeaconOn bool - /* Use relative prices rather than absolute prices because you - can get relative prices without traveling to each planet. */ - RelativePrices map [string] int - } + Commodities map[string]Commodity + Planets map[string]Planet + p2i, c2i map[string]int // Generated; not read from file + i2p, i2c []string // Generated; not read from file } func ReadData() (data planet_data) { - f, err := os.Open(*datafile) + f, err := os.Open(*planet_data_file) if err != nil { panic(err) } @@ -56,44 +87,252 @@ func ReadData() (data planet_data) { return } -func TradeValue(data planet_data, - from_index, to_index, commodity_index, quantity int) int { +/* This program operates by filling in a state table representing the best + * possible trips you could make; the ones that makes you the most money. + * This is feasible because we don't look at all the possible trips. + * We define a list of things that are germane to this game and then only + * consider the best outcome in each possible game state. + * + * Each cell in the table represents a state in the game. In each cell, + * we track two things: 1. the most money you could possibly have while in + * that state and 2. one possible way to get into that state with that + * amount of money. + * + * A basic analysis can be done with a two-dimensional table: location and + * fuel. planeteer-1.0 used this two-dimensional table. This version + * adds features mostly by adding dimensions to this table. + * + * 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. + */ - commodity := &data.Commodities[commodity_index] - if !commodity.CanSell { - return 0 +// The official list of dimensions: +const ( + // Name Num Size Description + Edens = iota // 1 3 # of Eden warp units (0 - 2 typically) + Cloaks // 2 2 # of Devices of Cloaking (0 or 1) + UnusedCargo // 3 4 # of unused cargo spaces (0 - 3 typically) + Fuel // 4 17 Reactor power left (0 - 16) + Location // 5 26 Location (which planet) + Hold // 6 15 Cargo bay contents (a *Commodity or nil) + NeedFighters // 7 2 Errand: Buy fighter drones (needed or not) + NeedShields // 8 2 Errand: Buy shield batteries (needed or not) + Visit // 9 2**N Visit: Stop by these N planets in the route + + NumDimensions +) + +func bint(b bool) int { + if b { + return 1 + } + return 0 +} + +func DimensionSizes(data planet_data) []int { + eden_capacity := data.Commodities["Eden Warp Units"].Limit + cloak_capacity := bint(*cloak) + 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) + 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 + for _, size := range dims { + sum += size + } + return sum +} + +type State struct { + funds, from int +} - from_planet := &data.Planets[from_index] - from_relative_price, from_available := from_planet.RelativePrices[commodity.Name] +func EncodeIndex(dims, addr []int) int { + index := addr[0] + for i := 1; i < len(dims); 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[i] = index % dims[i] + index /= dims[i] + } + addr[0] = index + return addr +} + +func FillStateCell(data planet_data, dims []int, table []State, addr []int) { +} + +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] + 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) + } + } + } + } + } + } + } + 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) []State { + table := make([]State, StateTableSize(dims)) + 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++ + fmt.Printf("\r%3.0f%%", 100 * work_done / work_units) + } + } + return table +} + +/* 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_planet := &data.Planets[to_index] - to_relative_price, to_available := to_planet.RelativePrices[commodity.Name] + to_relative_price, to_available := to.RelativePrices[commodity] if !to_available { return 0 } - from_absolute_price := from_relative_price * commodity.BasePrice - to_absolute_price := to_relative_price * commodity.BasePrice + 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) - return (sell_price - buy_price) * quantity - + 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 } -func FindBestTrades(data planet_data) [][]*Commodity { - best := make([][]*Commodity, len(data.Planets)) - for from_index := range data.Planets { - best[from_index] = make([]*Commodity, len(data.Planets)) - for to_index := range data.Planets { +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 - for commodity_index := range data.Commodities { - gain := TradeValue(data, from_index, to_index, commodity_index, 1) + price_list := data.Planets[from].RelativePrices + if len(data.Planets[to].RelativePrices) < len(data.Planets[from].RelativePrices) { + price_list = data.Planets[to].RelativePrices + } + for commodity := range price_list { + gain := TradeValue(data, + data.Planets[from], + data.Planets[to], + commodity, + 10000000, + 1) if gain > best_gain { - best[from_index][to_index] = &data.Commodities[commodity_index] + best[data.p2i[from]][data.p2i[to]] = commodity gain = best_gain } } @@ -102,17 +341,47 @@ func FindBestTrades(data planet_data) [][]*Commodity { return best } +// (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) + i := start_at + for e := range *m { + e2i[e] = i + i2e[i] = 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) + i := start_at + for e := range *m { + e2i[e] = i + i2e[i] = e + i++ + } + return e2i, i2e +} + func main() { flag.Parse() data := ReadData() + 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_index, from_planet := range data.Planets { - for to_index, to_planet := range data.Planets { + + for from := range data.Planets { + for to := range data.Planets { best_trade := "(nothing)" - if best_trades[from_index][to_index] != nil { - best_trade = best_trades[from_index][to_index].Name + 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_planet.Name, to_planet.Name, best_trade) + fmt.Printf("%s to %s: %s\n", from, to, best_trade) } } }