39 lines
761 B
Plaintext
39 lines
761 B
Plaintext
MODULE MutualRecursion;
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FROM InOut IMPORT WriteCard, WriteString, WriteLn;
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TYPE Fn = PROCEDURE(CARDINAL): CARDINAL;
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PROCEDURE F(n: CARDINAL): CARDINAL;
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BEGIN
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IF n=0 THEN RETURN 1;
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ELSE RETURN n-M(F(n-1));
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END;
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END F;
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PROCEDURE M(n: CARDINAL): CARDINAL;
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BEGIN
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IF n=0 THEN RETURN 0;
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ELSE RETURN n-F(M(n-1));
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END;
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END M;
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(* Print the first few values of one of the functions *)
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PROCEDURE Show(name: ARRAY OF CHAR; fn: Fn);
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CONST Max = 15;
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VAR i: CARDINAL;
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BEGIN
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WriteString(name);
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WriteString(": ");
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FOR i := 0 TO Max DO
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WriteCard(fn(i), 0);
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WriteString(" ");
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END;
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WriteLn;
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END Show;
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(* Show the first values of both F and M *)
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BEGIN
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Show("F", F);
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Show("M", M);
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END MutualRecursion.
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