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-- a simple boolean ant int counter
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2
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3
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node greycounter (x:bool) returns (out:bool);
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4
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var a,b:bool;
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let
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6
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a = false -> not pre(b);
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7
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b = false -> pre(a);
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out = a and b;
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9
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tel
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10
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11
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node intloopcounter (x:bool) returns (out:bool);
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12
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var time: int;
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13
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let
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14
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--! /machine_types/: (time, "uint8");
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15
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time = 0 -> if pre(time) = 3 then 0
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16
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else pre time + 1;
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out = (time = 2);
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18
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tel
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19
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20
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21
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--@ ensures OK;
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22
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node top (x:bool) returns (OK:bool);
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23
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var b,d:bool;
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24
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let
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b = greycounter(x);
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26
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d = intloopcounter(x);
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27
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OK = b = d;
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28
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--%PROPERTY OK;
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29
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tel
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