progs/fun2/fact.fun
author Christian Urban <christian.urban@kcl.ac.uk>
Fri, 24 Oct 2025 11:26:43 +0100
changeset 1018 fd6a64c53f0e
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permissions -rw-r--r--
updated
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// a simple factorial program
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// (including a tail recursive version)
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def fact(n: Int) : Int =
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  if n == 0 then 1 else n * fact(n - 1);
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def facT(n: Int, acc: Int) : Int =
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  if n == 0 then acc else facT(n - 1, n * acc);
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def facTi(n: Int) : Int = facT(n, 1);
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def top() : Void = {
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  print_int(fact(6));
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  print_char(',');
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  print_int(facTi(6));
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  print_char('\n')
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};
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top()
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