diff --git a/main.nim b/main.nim index e2d2b78..31fb878 100644 --- a/main.nim +++ b/main.nim @@ -1,4 +1,4 @@ -import algorithm, options, sequtils, sugar +import algorithm, math, options, tables, sequtils, sugar type @@ -15,13 +15,16 @@ type Die = tuple[color: Color, value: range[1..3]] + ScoreSet = array[Color, int] + Board = object squares: array[1..16, Square] camels: array[Color, range[1..16]] leader: Color + gameOver: bool -proc `[]`(b: var Board, idx: range[1..16]): var Square = +proc `[]`[T](b: var Board, idx: T): var Square = b.squares[idx] @@ -33,17 +36,18 @@ proc display(b: Board, start, stop: int) = echo lead, sq.tile.get else: echo lead, sq.camels - echo "\n" + echo "" -proc preRoll(b: var Board) = - let colors = [cGreen, cYellow, cPurple, cBlue, cRed] - var rolls = [range[1..16]3, 2, 3, 2, 1] +proc setLeader(b: var Board) = + b.leader = b[b.camels.max].camels[^1] # top camel in the last currently-occupied space - for (color, roll) in zip(colors, rolls): - let dest = roll + 1 + +proc setState[T](b: var Board, state: T) = + for (color, dest) in state: # note that `state` is ordered, as this determines stacking b[dest].camels.add(color) b.camels[color] = dest + b.setLeader proc advance(b: var Board, die: Die) = @@ -52,6 +56,11 @@ proc advance(b: var Board, die: Die) = startPos = b.camels[color] var prepend = false var endPos = startPos + roll + + if endPos > 16: # camel has passed the finish line + b.leader = color + b.gameOver = true + return if b[endPos].tile.isSome: endPos += int(b[endPos].tile.get) if b[endPos].tile.get == tBackward: prepend = true # if moving backward, we will prepend camel to the seq @@ -67,13 +76,12 @@ proc advance(b: var Board, die: Die) = b[startPos].camels[i .. ^1] = @[] for moved in subStack: b.camels[moved] = endPos - b.leader = b[b.camels.max][^1] # top camel in the last currently-occupied space - - break # breaking the outer loop here, not the inner + b.setLeader + break # breaking the outer loop here, not the inner - but only conditionally! gah! iterator allPermutations[T](x: seq[T]): seq[T] = - # returns all permutations of a given array. Order is wonky but we don't care. + # returns all permutations of a given seq. Order is wonky but we don't care. var workingCopy = x yield workingCopy while workingCopy.nextPermutation: # this mutates workingCopy @@ -83,9 +91,53 @@ iterator allPermutations[T](x: seq[T]): seq[T] = yield workingCopy +proc update(scores: var ScoreSet, toAdd: ScoreSet) = + for i, s in toAdd: + scores[i] += s + + +proc simOrdering(b: Board, ordering: seq[Color]): ScoreSet = + for color in ordering: + for roll in 1..3: + let d = (color, range[1..3](roll)) + let nextBoardState = b.dup(advance(d)) # make a copy instead of mutating + # only continue recursing if this is not the last die AND the game is not over + if ordering.len > 1 and not nextBoardState.gameOver: + let nextResult = simOrdering(nextBoardState, ordering[1 .. ^1]) + result.update(nextResult) + else: + inc result[nextBoardState.leader] + + +iterator possibleFutures(dice: seq[Color]): seq[Die] + # iterate over all possible sequences of die rolls. Each outcome + # is returned as a 5-sequence of (color, number) tuples. + yield (cRed, range[1..3]3) + + +proc sumLegResults(b: Board, diceRemaining: seq[Color]): ScoreSet = + var count = 0 + for perm in diceRemaining.allPermutations: + let permResult = simOrdering(b, perm) + result.update(permResult) + let total = result.sum + stdout.write("simulated: " & $total & "\r") + stdout.flushFile + count += 1 + echo "" + echo count + + var b: Board b.display(1, 5) -b.preRoll -let c = b.dup(advance((cRed, range[1..3]3))) + +b.setState({cGreen: 4, cYellow: 3, cPurple: 4, cBlue: 3, cRed: 2}) b.display(1, 5) -c.display(1, 5) + +b.advance((cRed, range[1..3](2))) +b.display(1, 5) + +let r = b.sumLegResults(@[cRed, cGreen, cBlue, cYellow, cPurple]) +let total = r.sum +for i, c in r: + echo Color(i), ": ", (c / total).round(4) * 100, "% (", c, " / ", total, ")"