32 lines
609 B
Modula-2
32 lines
609 B
Modula-2
IMPLEMENTATION MODULE random;
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FROM Unix IMPORT getpid, time;
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TYPE index = [0..54];
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VAR X: ARRAY index OF CARDINAL;
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k, j: index;
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PROCEDURE Random(): CARDINAL;
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BEGIN
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IF k+1 > 54 THEN k := 0; ELSE INC(k) END;
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IF j+1 > 54 THEN j := 0; ELSE INC(j) END;
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X[k] := X[k] + X[j];
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RETURN X[k]
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END Random;
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PROCEDURE Uniform (lwb, upb: CARDINAL): CARDINAL;
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BEGIN
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IF upb <= lwb THEN RETURN lwb; END;
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RETURN lwb + (Random() MOD (upb - lwb + 1));
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END Uniform;
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BEGIN
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X[0] := time(NIL);
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X[0] := CARDINAL(getpid()) * X[0];
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FOR k := 1 TO 54 DO
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X[k] := X[k-1] * 1297;
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END;
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k := 54;
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j := 30;
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END random.
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