45 lines
1.3 KiB
Plaintext
45 lines
1.3 KiB
Plaintext
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/************************************************/
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/* This program tests the STKSIZ function while */
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/* evaluating a RECURSIVE procedure. */
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/************************************************/
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ack:
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procedure options(main,stack(2000));
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declare
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(m,n) fixed,
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(maxm,maxn) fixed,
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ncalls decimal(6),
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(curstack, stacksize) fixed,
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stksiz entry returns(fixed);
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put skip list('Type max m,n: ');
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get list(maxm,maxn);
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do m = 0 to maxm;
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do n = 0 to maxn;
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ncalls = 0;
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curstack = 0;
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stacksize = 0;
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put edit('Ack(',m,',',n,')=',ackermann(m,n),
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ncalls,' Calls,',stacksize,' Stack Bytes')
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(skip,a,2(f(2),a),f(6),f(7),a,f(4),a);
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end;
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end;
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stop;
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ackermann:
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procedure(m,n) returns(fixed) recursive;
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declare
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(m,n) fixed;
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ncalls = ncalls + 1;
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curstack = stksiz();
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if curstack > stacksize then
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stacksize = curstack;
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if m = 0 then
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return(n+1);
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if n = 0 then
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return(ackermann(m-1,1));
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return(ackermann(m-1,ackermann(m,n-1)));
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end ackermann;
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end ack;
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