--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main_templates5/bf.scala	Mon Nov 02 02:31:44 2020 +0000
@@ -0,0 +1,188 @@
+// Core Part about an Interpreter for 
+// the Brainf***++ language
+//==============================================
+
+
+object CW10a {
+
+
+// representation of Bf memory 
+
+type Mem = Map[Int, Int]
+
+
+// (1) Write a function that takes a file name as argument and
+// and requests the corresponding file from disk. It Returns the
+// content of the file as a String. If the file does not exists,
+// the function should Return the empty string.
+
+import io.Source
+import scala.util._
+
+def load_bff(name: String) : String = ???
+
+
+
+// (2) Complete the functions for safely reading  
+// and writing brainf***++ memory. Safely read should
+// Return the value stored in the Map for a given memory
+// pointer, provided it exists; otherwise it Returns 0. The
+// writing function generates a new Map with the
+// same data, except at the given memory pointer the
+// value v is stored.
+
+
+def sread(mem: Mem, mp: Int) : Int = ???
+
+def write(mem: Mem, mp: Int, v: Int) : Mem = ???
+
+
+
+// (3) Implement the two jumping instructions in the 
+// brainf***++ language. In jumpRight, given a program and 
+// a program counter move the program counter to the right 
+// until after the *matching* ]-command. Similarly, 
+// jumpLeft implements the move to the left to just after
+// the *matching* [-command.
+
+def jumpRight(prog: String, pc: Int, level: Int) : Int = ???
+
+def jumpLeft(prog: String, pc: Int, level: Int) : Int = ???
+
+
+// testcases
+//jumpRight("""--[..+>--],>,++""", 3, 0)         // => 10
+//jumpLeft("""--[..+>--],>,++""", 8, 0)          // => 3
+//jumpRight("""--[..[+>]--],>,++""", 3, 0)       // => 12
+//jumpRight("""--[..[[-]+>[.]]--],>,++""", 3, 0) // => 18
+//jumpRight("""--[..[[-]+>[.]]--,>,++""", 3, 0)  // => 22 (outside)
+//jumpLeft("""[******]***""", 7, 0)              // => -1 (outside)
+
+
+
+// (4) Complete the compute function that interprets (runs) a brainf***++
+// program: the arguments are a program (represented as a string), a program 
+// counter, a memory counter and a brainf***++ memory. It Returns the
+// memory at the stage when the execution of the brainf***++ program
+// finishes. The interpretation finishes once the program counter
+// pc is pointing to something outside the program string.
+// If the pc points to a character inside the program, the pc, 
+// memory pointer and memory need to be updated according to 
+// rules of the brainf***++ language. Then, recursively, the compute 
+// function continues with the command at the new program
+// counter. 
+//
+// Implement the run function that calls compute with the program
+// counter and memory counter set to 0.
+
+
+def compute(prog: String, pc: Int, mp: Int, mem: Mem) : Mem = ???
+
+def run(prog: String, m: Mem = Map()) = ???
+
+
+
+// some sample bf/bf++-programs collected from the Internet
+//==========================================================
+
+
+// some contrived (small) programs
+//---------------------------------
+
+// clears the 0-cell
+//run("[-]", Map(0 -> 100))    // Map will be 0 -> 0
+
+// moves content of the 0-cell to 1-cell
+//run("[->+<]", Map(0 -> 10))  // Map will be 0 -> 0, 1 -> 10
+
+
+// copies content of the 0-cell to 2-cell and 4-cell
+//run("[>>+>>+<<<<-]", Map(0 -> 42))    // Map(0 -> 0, 2 -> 42, 4 -> 42)
+
+
+// prints out numbers 0 to 9
+//run("""+++++[->++++++++++<]>--<+++[->>++++++++++<<]>>++<<----------[+>.>.<+<]""")
+
+// bf++ program calculating the cube-function, 10 * 10 * 10 = 1000
+//run("""++++++++++#>+***#""")           // Map(0 -> 10, 1 -> 1000)
+
+
+// bf++ program copies 3 from 0-cell to to cells 1, 4, 5, 6 and 7
+// (note that because of how the program wprks cell 1 will contain 7) 
+//run("""+++>+@+@+@+@+@""")   // Map(0 -> 3, 1 -> 7, 4 -> 3, 5 -> 3, 6 -> 3, 7 -> 3)
+
+
+
+// some more "useful" programs
+//-----------------------------
+
+// hello world program 1
+//run("""++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++
+//       ..+++.>>.<-.<.+++.------.--------.>>+.>++.""")
+
+// hello world program 2
+//run("""++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>+
+//       +.<<+++++++++++++++.>.+++.------.--------.>+.>.""")
+
+// hello world program 3
+//run("""+++++++++[>++++++++>+++++++++++>+++++<<<-]>.>++.+++++++..
+//       +++.>-.------------.<++++++++.--------.+++.------.--------.>+.""")
+
+ 
+// draws the Sierpinski triangle
+//run(load_bff("sierpinski.bf"))
+
+
+//fibonacci numbers below 100
+//run("""+++++++++++
+//      >+>>>>++++++++++++++++++++++++++++++++++++++++++++
+//      >++++++++++++++++++++++++++++++++<<<<<<[>[>>>>>>+>
+//      +<<<<<<<-]>>>>>>>[<<<<<<<+>>>>>>>-]<[>++++++++++[-
+//      <-[>>+>+<<<-]>>>[<<<+>>>-]+<[>[-]<[-]]>[<<[>>>+<<<
+//      -]>>[-]]<<]>>>[>>+>+<<<-]>>>[<<<+>>>-]+<[>[-]<[-]]
+//      >[<<+>>[-]]<<<<<<<]>>>>>[+++++++++++++++++++++++++
+//      +++++++++++++++++++++++.[-]]++++++++++<[->-<]>++++
+//      ++++++++++++++++++++++++++++++++++++++++++++.[-]<<
+//      <<<<<<<<<<[>>>+>+<<<<-]>>>>[<<<<+>>>>-]<-[>>.>.<<<
+//      [-]]<<[>>+>+<<<-]>>>[<<<+>>>-]<<[<+>-]>[<+>-]<<<-]""")
+
+//outputs the square numbers up to 10000
+//run("""++++[>+++++<-]>[<+++++>-]+<+[>[>+>+<<-]++>>[<<+>>-]>>>[-]++>[-]+
+//       >>>+[[-]++++++>>>]<<<[[<++++++++<++>>-]+<.<[>----<-]<]
+//       <<[>>>>>[>>>[-]+++++++++<[>-<-]+++++++++>[-[<->-]+[<<<]]<[>+<-]>]<<-]<<-]""")
+
+
+// calculates 2 to the power of 6 
+//(example from a C-to-BF compiler at https://github.com/elikaski/BF-it)
+//run(""">>[-]>[-]++>[-]++++++><<<>>>>[-]+><>[-]<<[-]>[>+<<+>-]>[<+>-]
+//       <><[-]>[-]<<<[>>+>+<<<-]>>>[<<<+>>>-][-]><<>>[-]>[-]<<<[>>[-]
+//       <[>+>+<<-]>[<+>-]+>[[-]<-<->>]<<<-]>>[<<+>>-]<<[[-]>[-]<<[>+>
+//       +<<-]>>[<<+>>-][-]>[-]<<<<<[>>>>+>+<<<<<-]>>>>>[<<<<<+>>>>>-]
+//       <<>>[-]>[-]<<<[>>>+<<<-]>>>[<<[<+>>+<-]>[<+>-]>-]<<<>[-]<<[-]
+//       >[>+<<+>-]>[<+>-]<><[-]>[-]<<<[>>+>+<<<-]>>>-[<<<+>>>-]<[-]>[-]
+//       <<<[>>+>+<<<-]>>>[<<<+>>>-][-]><<>>[-]>[-]<<<[>>[-]<[>+>+<<-]>
+//       [<+>-]+>[[-]<-<->>]<<<-]>>[<<+>>-]<<][-]>[-]<<[>+>+<<-]>>[<<+>
+//       >-]<<<<<[-]>>>>[<<<<+>>>>-]<<<<><>[-]<<[-]>[>+<<+>-]>[<+>-]<>
+//       <[-]>[-]>[-]<<<[>>+>+<<<-]>>>[<<<+>>>-]<<>>[-]>[-]>[-]>[-]>[-]>
+//       [-]>[-]>[-]>[-]>[-]<<<<<<<<<<>>++++++++++<<[->+>-[>+>>]>[+[-<+
+//       >]>+>>]<<<<<<]>>[-]>>>++++++++++<[->-[>+>>]>[+[-<+>]>+>>]<<<<<
+//       ]>[-]>>[>++++++[-<++++++++>]<.<<+>+>[-]]<[<[->-<]++++++[->++++
+//       ++++<]>.[-]]<<++++++[-<++++++++>]<.[-]<<[-<+>]<<><<<""")
+
+
+
+// a Mandelbrot set generator in brainf*** written by Erik Bosman
+// (http://esoteric.sange.fi/brainfuck/utils/mandelbrot/)
+//
+//run(load_bff("mandelbrot.bf"))
+
+
+// a benchmark program (counts down from 'Z' to 'A')
+//
+//run(load_bff("benchmark.bf"))
+
+// calculates the Collatz series for numbers from 1 to 30
+//
+//run(load_bff("collatz.bf"))
+
+}