Mutual recursion: Difference between revisions

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m →‎{{header|REXX}}: optimized all three programs, added whitespace, used templates for the output sections.
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This version uses vertical formatting of the output.
This version uses vertical formatting of the output.
<lang rexx>/*REXX program shows mutual recursion (via the Hofstadter Male and Female sequences). */
<lang rexx>/*REXX program shows mutual recursion (via the Hofstadter Male and Female sequences). */
parse arg lim .; if lim='' then lim=40; w=length(lim); pad=left('', 20)
parse arg lim .; if lim='' then lim= 40; w= length(lim); pad= left('', 20)


do j=0 to lim; jj=right(j, w); ff=right(F(j), w); mm=right(M(j), w)
do j=0 for lim+1; jj= right(j, w); ff= right(F(j), w); mm= right(M(j), w)
say pad 'F('jj") =" ff pad 'M('jj") =" mm
say pad 'F('jj") =" ff pad 'M('jj") =" mm
end /*j*/
end /*j*/
exit /*stick a fork in it, we're all done. */
exit /*stick a fork in it, we're all done. */
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F: procedure; parse arg n; if n==0 then return 1; return n - M( F(n-1) )
F: procedure; parse arg n; if n==0 then return 1; return n - M( F(n-1) )
M: procedure; parse arg n; if n==0 then return 0; return n - F( M(n-1) )</lang>
M: procedure; parse arg n; if n==0 then return 0; return n - F( M(n-1) )</lang>
'''output''' &nbsp; when using the default input of: &nbsp; <tt> 40 </tt>
{{out|output|text=&nbsp; when using the default input of: &nbsp; &nbsp; <tt> 40 </tt>}}
<pre>
<pre>
F( 0) = 1 M( 0) = 0
F( 0) = 1 M( 0) = 0
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<lang rexx>/*REXX program shows mutual recursion (via the Hofstadter Male and Female sequences). */
<lang rexx>/*REXX program shows mutual recursion (via the Hofstadter Male and Female sequences). */
parse arg lim .; if lim=='' then lim=40 /*assume the default for LIM? */
parse arg lim .; if lim=='' then lim=40 /*assume the default for LIM? */
w=length(lim); $m.=.; $m.0=0; $f.=.; $f.0=1; Js=; Fs=; Ms=
w= length(lim); $m.=.; $m.0= 0; $f.=.; $f.0= 1; Js=; Fs=; Ms=


do j=0 to lim
do j=0 for lim+1
Js=Js right(j, w); Fs=Fs right(F(j), w); Ms=Ms right(M(j), w)
Js= Js right(j, w); Fs= Fs right( F(j), w); Ms= Ms right( M(j), w)
end /*j*/
end /*j*/
say 'Js=' Js /*display the list of Js to the term.*/
say 'Js=' Js /*display the list of Js to the term.*/
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exit /*stick a fork in it, we're all done. */
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
/*──────────────────────────────────────────────────────────────────────────────────────*/
F: procedure expose $m. $f.; parse arg n; if $f.n==. then $f.n=n-M(F(n-1)); return $f.n
F: procedure expose $m. $f.; parse arg n; if $f.n==. then $f.n= n-M(F(n-1)); return $f.n
M: procedure expose $m. $f.; parse arg n; if $m.n==. then $m.n=n-F(M(n-1)); return $m.n</lang>
M: procedure expose $m. $f.; parse arg n; if $m.n==. then $m.n= n-F(M(n-1)); return $m.n</lang>
'''output''' &nbsp; when using the default input of: &nbsp; <tt> 99 </tt>
{{out|output|text=&nbsp; when using the default input of: &nbsp; &nbsp; <tt> 99 </tt>}}
<pre>
<pre>
Js= 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
Js= 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
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/*───────────────── If LIM is negative, a single result is shown for the abs(lim) entry.*/
/*───────────────── If LIM is negative, a single result is shown for the abs(lim) entry.*/


parse arg lim .; if lim=='' then lim=99; aLim=abs(lim)
parse arg lim .; if lim=='' then lim= 99; aLim= abs(lim)
w=length(aLim); $m.=.; $m.0=0; $f.=.; $f.0=1; Js=; Fs=; Ms=
w= length(aLim); $m.=.; $m.0= 0; $f.=.; $f.0= 1; Js=; Fs=; Ms=


do j=0 to Alim
do j=0 for Alim+1
Js=Js right(j, w); Fs=Fs right(F(j), w); Ms=Ms right(M(j), w)
Js= Js right(j, w); Fs= Fs right( F(j), w); Ms= Ms right( M(j), w)
end /*j*/
end /*j*/


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exit /*stick a fork in it, we're all done. */
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
/*──────────────────────────────────────────────────────────────────────────────────────*/
F: procedure expose $m. $f.; parse arg n; if $f.n==. then $f.n=n-M(F(n-1)); return $f.n
F: procedure expose $m. $f.; parse arg n; if $f.n==. then $f.n= n-M(F(n-1)); return $f.n
M: procedure expose $m. $f.; parse arg n; if $m.n==. then $m.n=n-F(M(n-1)); return $m.n</lang>
M: procedure expose $m. $f.; parse arg n; if $m.n==. then $m.n= n-F(M(n-1)); return $m.n</lang>
'''output''' &nbsp; when using the input of: &nbsp; <tt> -70000 </tt>
{{out|output|text=&nbsp; when using the input of: &nbsp; &nbsp; <tt> -70000 </tt>}}
<pre>
<pre>
J(70000)= 70000
J(70000)= 70000
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M(70000)= 43262
M(70000)= 43262
</pre>
</pre>
'''output''' &nbsp; when using the input of a negative &nbsp; <big>¼</big> &nbsp; million: &nbsp; <tt> -250000 </tt>
{{out|output|text=&nbsp; when using the input of a negative &nbsp; <big>¼</big> &nbsp; million: &nbsp; &nbsp; <tt> -250000 </tt>}}
<pre>
<pre>
J(250000)= 250000
J(250000)= 250000
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