--- a/assignment2021scala/core3/postfix2.scala Fri Apr 26 17:29:30 2024 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,69 +0,0 @@
-// Shunting Yard Algorithm
-// including Associativity for Operators
-// =====================================
-
-object C3b {
-
-
-// type of tokens
-type Toks = List[String]
-
-// helper function for splitting strings into tokens
-def split(s: String) : Toks = s.split(" ").toList
-
-// left- and right-associativity
-abstract class Assoc
-case object LA extends Assoc
-case object RA extends Assoc
-
-
-// power is right-associative,
-// everything else is left-associative
-def assoc(s: String) : Assoc = s match {
- case "^" => RA
- case _ => LA
-}
-
-
-// the precedences of the operators
-val precs = Map("+" -> 1,
- "-" -> 1,
- "*" -> 2,
- "/" -> 2,
- "^" -> 4)
-
-// the operations in the basic version of the algorithm
-val ops = List("+", "-", "*", "/", "^")
-
-// (3) Implement the extended version of the shunting yard algorithm.
-// This version should properly account for the fact that the power
-// operation is right-associative. Apart from the extension to include
-// the power operation, you can make the same assumptions as in
-// basic version.
-
-def syard(toks: Toks, st: Toks = Nil, out: Toks = Nil) : Toks = ???
-
-
-// test cases
-// syard(split("3 + 4 * 8 / ( 5 - 1 ) ^ 2 ^ 3")) // 3 4 8 * 5 1 - 2 3 ^ ^ / +
-
-
-// (4) Implement a compute function that produces an Int for an
-// input list of tokens in postfix notation.
-
-def compute(toks: Toks, st: List[Int] = Nil) : Int = ???
-
-
-// test cases
-// compute(syard(split("3 + 4 * ( 2 - 1 )"))) // 7
-// compute(syard(split("10 + 12 * 33"))) // 406
-// compute(syard(split("( 5 + 7 ) * 2"))) // 24
-// compute(syard(split("5 + 7 / 2"))) // 8
-// compute(syard(split("5 * 7 / 2"))) // 17
-// compute(syard(split("9 + 24 / ( 7 - 3 )"))) // 15
-// compute(syard(split("4 ^ 3 ^ 2"))) // 262144
-// compute(syard(split("4 ^ ( 3 ^ 2 )"))) // 262144
-// compute(syard(split("( 4 ^ 3 ) ^ 2"))) // 4096
-// compute(syard(split("( 3 + 1 ) ^ 2 ^ 3"))) // 65536
-
-}