• Version:
  In order to support further enhancements, any changes will be associated with a version number. The version of a respective file is given by the line starting with .version. The version of the current revison is 1.0.
• Comments:
  Comments provide human-readable information about the respective instance, e.g. a short description, authors, or similar. A comment line starts with a # character. All comment lines will be ignored by programs.
• Number of Variables:
  The line starting with .varnum signifies the number n of variables (lines) of the respective function (circuit). The number has to be a positive integer.
• Variables:
  The line starting with .variables signifies the ordered list of identifiers for the respective variables (lines). An identifier has to be a sequence of letters, digits and underscores. In total, n different identifiers have to be defined in a .variables line (separated by spaces).
• Inputs/Outputs:
  The line starting with .inputs (.outputs) signifies the ordered list of names of the respective inputs (outputs). A name has to be a sequence of letters, digits and underscores. In total, n different names have to be defined in a .inputs (outputs) line (separated by spaces). Defining the inputs (outputs) is optional. By default the names of inputs (outputs) is equal to the respective identifier of the variable.
• Constant Inputs:
  Constant inputs can be definied by a line starting with .constants followed by a string containing the values for the input constants (1 for constant one, 0 for constant zero and - if the respective input line is not constant) in the order they appear without any spaces. Defining constant inputs is optional. By default all inputs are not constants (i.e. for each input the value is -).
• Garbage Outputs:
  Garbage outputs can be definied by a line starting with .garbage followed by a string indicating whether an output is garbage or not (1' if the output is garbage and - if the output is not garbage) in the order they appear without any spaces. Defining garbage outputs is optional. By default all outputs are not garbage (i.e. for each output the value is -).

           1  # Embedded AND function
            2 .version 1.0
            3 .numvars 3
            4 .variables x y z
            5 .inputs 1 a b
            6 .outputs f g1 g2
            7 .constants 1--
            8 .garbage -11
            9 .begin
           10 ---
           11 ---
           12 ---
           13 ---
           14 ---
           15 0--
           16 0--
           17 0--
           18 1--
           19 .end

Circuit Specification
A reversible circuit is specified by all its gates. The specification lists the gates in the order they appear in the actual design. In the current version we distinguish five different gates:

• Multiple Control Toffoli gates (MCT):
  A (multiple control) Toffoli gate is signified by the character t and an integer indicating the size of the gate followed by a list of variables for the respective lines such that the the target line is at the end of the list. Note that Toffoli gates include (controled) NOT gates as well.
  Example: t3 a b c
• Multiple Control Fredkin gate (MCF):
  A (multiple control) Fredkin gate is signified by the character f and an integer indicating the size of the gate followed by a list of variables for the respective lines such that the the targets of the gates are at the end of the list.
  Example: f3 a b c
• Peres gate (P):
  A Peres gate is signified by the character p and an integer indicating the size of the gate followed by a list of variables for the respective lines such that the the targets of the gates are at the end of the list.
  Example: p3 a b c
• V gate:
  A V gate - one of the elementary quantum gates (EQ) - is signified by the character v and an integer indicating the size of the gate (i.e. 2) followed by a list of variables for the respective lines such that the the target line is at the end of the list.
  Example: v2 a b
• V+ gate:
  A V+ gate - one of the elementary quantum gates (EQ) - is signified by the characters \verb-v+- and an integer indicating the size of the gate (i.e. ) followed by a list of variables for the respective lines such that the the target line is at the end of the list.
  Example: v+2 a b

Example:

           1  # AND circuit
            2 .version 1.0
            3 .numvars 3
            4 .variables x y z
            5 .inputs 1 a b
            6 .outputs f g1 g2
            7 .constants 1--
            8 .garbage -11
            9 .begin
           10 t3 y z x
           11 t1 x
           12 .end
    
    

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