Differences

This shows you the differences between two versions of the page.

--- pp:2023:scala:l06 [2023/04/07 15:49]
alexandra.udrescu01
+++ pp:2023:scala:l06 [2023/04/08 07:49] (current)
pdmatei
@@ Line 3: / Line 3: @@
 ==== 5-Tic-Tac-Toe ====
-**Tic Tac Toe** is usually played on a 3x3 board, marking positions by each player in rounds. Our game is slightly different:
+**Tic Tac Toe** is usually played on a 3x3 board, marking positions by each player in rounds. Our game is slightly different (usually called 5-in-a-row):
   * it can be played on a square board of any size **larger or equal to 5**.
   * A player wins if it has marked a line, column or diagonal of **5 consecutive positions** in a row.
@@ Line 30: / Line 30: @@
   * In your project template, ''X'' is encoded as the **first** player (''One''), and ''0'', as ''Two''.
+<code scala>
+trait Player {}
+case object One extends Player {
+  override def toString: String = "X"
+}
+case object Two extends Player {
+  override def toString: String = "0"
+}
+case object Empty extends Player {
+  override def toString: String = "."
+}
+</code>
   * A ''Board'' is encoded as a List of Lists of **positions** (i.e. a matrix), where a position can be ''One'', ''Two'' or ''Empty''. We make no distinction in the code between a position and a player, although ''Empty'' cannot be seen as a valid player. This makes the code slightly easier to write.
+<code scala>
+type Line = List[Player]
+type BoardList = List[Line]
+case class Board(b: BoardList) {
+  override def toString: String = ???
+}
+</code>
 ==== Tasks ====
+The following functions have a given signature. However, it is up to the student to decide whether these will be methods of a class or just simple functions.
 **6.1.1.** Write a function which converts a string into a ''Board''. As a helper, you can use ''_.split( c )'' where c is a separator string, and ''_.toList''. The best solution is to use a combination of ''map'' calls with the above mentioned functions. A string is encoded exactly as in the examples shown above:
@@ Line 47: / Line 68: @@
       }
     ???
+}
 </code>
 **6.1.2.** Write a function which checks if a position on the board is free. Recall that list indexing can be done using ''l(_)''. Positions are numbered from 0.
 <code scala>
-def isFree(x:Int, y:Int, b:Board):Boolean = ???
+def isFree(x:Int, y:Int):Boolean = ???
 </code>
 **6.1.3.** Write a function which returns the //opponent// of a player:
 <code scala>
-def complement(p: Player): Player =
+def complement(p: Player): Player = ???
 </code>
-**6.1.4.** Write a function which converts a board to a string, following the same strategy. **Important:** this function will be used throughout the tests. Make sure string doesn't end with '\n'. Hint: instead of ''foldRight'', you can use ''reduce'' which works quite similarly, but without requiring an accumulator.
+**6.1.4.** We want to write a function which converts a board to a string, following the same strategy. Complete the ''toString'' in the Board class. Hint: instead of ''foldRight'', you can use ''reduce'' which works quite similarly, but without requiring an accumulator.
-<code scala>
-def show(b: Board): String = ???
-</code>
 **6.1.5.** Write a function which returns the //columns// of a board:
 <code scala>
-def getColumns(b:Board): Board = ???
+def getColumns: Board = ???
 </code>
 **6.1.6.** Implement the following two functions for extracting the first and second diagonal, as lines, from a board. Hint: use for comprehensions.
 <code scala>
-def getFstDiag(b:Board): Line = ???
+def getFstDiag(): Line = ???
-def getSndDiag(b:Board): Line = ???
+def getSndDiag(): Line = ???
 </code>
 **6.1.7.** Implement the following functions for extracting diagonals above/below the first/second diagonal, as lines. It's not really necessary to make sure that at least 5 positions are available, for now. Hint: if one function must be implemented with element-by-element iteration, the three other can be implemented using each-other, as single-line calls.
 <code scala>
-def getAboveFstDiag(b: Board): List[Line] = ???
+def getAboveFstDiag: List[Line] = ???
-def getBelowFstDiag(b: Board): List[Line] = ???
+def getBelowFstDiag: List[Line] = ???
-def getAboveSndDiag(b: Board): List[Line] = ???
+def getAboveSndDiag: List[Line] = ???
-def getBelowSndDiag(b: Board): List[Line] = ???
+def getBelowSndDiag: List[Line] = ???
 </code>
 **6.1.8.** Write a function which checks if a player is the winner. Hint: functions ''l.forall(_)'' and ''l.exists(_)'' may be very helpful, together with patterns.
 <code scala>
-def winner(p: Player)(b: Board): Boolean =
+def winner(p: Player): Boolean = ???
 </code>
 **6.1.9.** Write a function which updates a position from the board, with a given player. The position need not be empty and you are not required to check this. Hint: re-use an inner aux-function together with ''take'' and ''drop''.
 <code scala>
-def update(p: Player)(ln: Int, col: Int, b: Board) : Board = ???
+def update(p: Player)(ln: Int, col: Int) : Board = ???
 </code>
-**6.1.10.** Write a function which generates all possible next-moves for any of the two players. A next-move consists in a new board, where the player-at-hand played his move. The order in which you generate next-moves is not important.
+**6.1.10.** Write a function which generates all possible next-moves for any of the two players. A next-move consists in a new board, where the player-at-hand played his move.
 <code scala>
-def next(p: Player)(b: Board): List[Board] = ???
+def next(p: Player): List[Board] = ???
 </code>
@@ Line 103: / Line 121: @@
 Use the following board configurations to test your solutions:
 <code scala>
-    todo
+val t1 =
+  """X0X0X0
+    |0X0X0X
+    |X0X0X0
+    |.XX0..
+    |X00...
+    |X0X0X0""".stripMargin
+val t2 =
+  """......
+    |......
+    |......
+    |.XX...
+    |.0000.
+    |......""".stripMargin
+val t3 =
+  """0X0X0.
+    |000.X0
+    |0.0X..
+    |0..0..
+    |0X..0X
+    |...X..""".stripMargin
 </code>