+ This game is played in two rounds, + on an empty eleven-space board. + The first round is played on {"Red's"} board, the second is played on {"Blue's"}. +
+ +
+ On {"Red's"} board, {"Red's"} goal is to maximize the value of the expression.
+ {" Blue's"} goal is to minimize it.
+
+ Players take turns placing the fourteen symbols 0123456789+-×÷
+ on the board, with the maximizing player taking the first move.
+
+ A {"board's"} syntax must always be valid, and + the following rules are enforced: +
+ ++-×÷ may not be next to one another, and may not be at the end slots.- (negative) must have a number as an argument. Therefore, it cannot be left of an operator (like -×), and it may not be in the rightmost slot.+ may not be used.0 may not follow ÷.
+ This prevents most cases of zero-division, but {"isn't perfect"}.
+ ÷-0 will result in an invalid board (causing a draw),
+ and ÷0_+ is forbidden despite being valid syntax once the empty slot is filled.
+ This is done to simplyify game logic, and might be improved later.
+ step_min() is called once per turn with the {"board's"} current state. This function must return an Action that aims to minimize the total value of the board.step_max() is just like step_min, but should aim to maximize the value of the board. + Agents are written in Rhai, a wonderful embedded scripting language powered by Rust. + Basic language features are outlined below. +
+;return to return a value from a function.print(anything) - Prints to the output panel. Prefer this over debug.debug(anything) - Prints to the output panel. Includes extra debug info.() is the {"\"none\""} type, returned by some methods above.for i in 0..5 {"{}"} will iterate five times, with i = 0, 1, 2, 3, 4for i in 0..=5 {"{}"} will iterate six times, with i = 0, 1, 2, 3, 4, 5let a = []; initializes an empty array.a.push(value) adds a value to the end of an arraya.pop() removes a value from the end of an array and returns ita[0] returns the first item of an arraya[1] returns the second item of an arrayAction(symbol, position) - Creates a new action that places symbol at position. Valid symbols are 01234567890+-/*. Both 0 and {"\"0\""} are valid symbols.board.can_play(action) - Checks if an action is valid. Returns a boolean.board.size() - Return the total number of spots on this board.board.free_spots() - Count the number of free spots on the board.board.play(action) - Apply the given action on this board. This mutates the board, but does NOT make the move in the game. The only way to commit to an action is to return it from step_min or step_max.
+ This method lets you compute potential values of a board when used with board.evaluate().
+ board.ith_free_slot(idx) - Returns the index of the nth free slot on this board. Returns -1 if no such slot exists.board.contains(symbol) - Checks if this board contains the given symbol. Returns a boolean.board.evaluate() - Return the value of a board if it can be computed. Returns () otherwise.board.free_spots_idx(action) - Checks if an action is valid. Returns a boolean.for i in board {"{ ... }"} - Iterate over all slots on this board. Items are returned as strings, empty slots are the empty string ({"\"\""})is_op(symbol) - Returns true if symbol is one of +-*/rand_symb() - Returns a random symbol (number or operation)rand_op() - Returns a random operator symbol (one of +-*/)rand_action() - Returns a random Actionrand_int(min, max) - Returns a random integer between min and max, including both endpoints.rand_bool(probability) - Return true with the given probability. Otherwise return false.rand_shuffle(array) - Shuffle the given arrayfor p in permutations(array, 5) {"{}"} - Iterate over all permutations of 5 elements of the given array.