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