aparler/RosettaCodeData
1
0
Fork 0
Code Issues 12 Pull requests 3 Projects Releases Packages Wiki Activity Actions

Data commit

Browse source
This commit is contained in:
Ingy döt Net 2023-07-01 11:58:00 -04:00
parent 7387c8f97b
commit cb5bb5e222
199093 changed files with 3378972 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

54
Task/Parsing-RPN-to-infix-conversion/PL-I/parsing-rpn-to-infix-conversion.pli Normal file
View file

@ -0,0 +1,54 @@
/* Uses a push-down pop-up stack for the stack (instead of array) */
cvt: procedure options (main); /* 10 Sept. 2012 */
declare (true initial ('1'b), false initial ('0'b) ) bit (1);
declare list character (1) controlled, written bit (1) controlled;
declare (RPN, out) character (100) varying;
declare s character (1);
declare input_priority (5) fixed (1) static initial (1, 1, 2, 2, 3);
declare stack_priority (5) fixed (1) static initial (1, 1, 2, 2, 4);
declare (i, ki, kl) fixed binary;
put ('Convert a Reverse Polish expression to orthodox.');
put skip list ('Enclose the expression in apostrophes:');
get list (RPN);
put skip list ('The original Reverse Polish expression = ' || RPN);
out = '';
allocate list, written;
list = substr(RPN, length(RPN), 1); written = false;
translation:
do i = length (RPN)-1 to 1 by -1;
s = substr(RPN, i, 1);
if s = ' ' then iterate;
ki = index('+-*/^', s);
kl = index('+-*/^', list);
if ki > 0 then /* we have an operator */
do;
if input_priority (ki) < stack_priority (kl) then
do; /* transfer ')' to list, then operator. */
allocate list, written;
list = '('; written = false;
out = ')' || out;
end;
allocate list, written;
list = s; written = false;
end;
else /* It's a variable name */
do;
out = s || out;
next_list:
if allocation(list) > 0 then if written then free written, list;
if allocation(list) > 0 then if list = '(' then
do; out = list || out; free written, list; end;
if allocation (list) = 0 then leave translation;
if written then go to next_list;
written = true;
out = list || out; /* Output an operator. */
end;
put skip edit ('INPUT=' || s) (a); call show_stack;
put edit (' OUTPUT=', out) (col(30), 2 a);
end;
put skip list ('ALGEBRAIC EXPRESSION=', out);
end cvt;