tasks a-s

Task/Semordnilap/PL-I/semordnilap.pli

@@ -0,0 +1,41 @@
+find: procedure options (main); /* 20/1/2013 */
+   declare word character (20) varying controlled;
+   declare dict(*) character (20) varying controlled;
+   declare 1 pair controlled,
+              2 a character (20) varying, 2 b character (20) varying;
+   declare (i, j) fixed binary;
+   declare in file;
+
+   open file(in) title ('/UNIXDICT.TXT,type(LF),recsize(100)');
+   on endfile (in) go to completed_read;
+   do forever;
+      allocate word;
+      get file (in) edit (word) (L);
+   end;
+
+completed_read:
+   free word; /* because at the final allocation, no word was stored. */
+   allocate dict(allocation(word));
+   do i = 1 to hbound(dict,1);
+      dict(i) = word; free word;
+   end;
+
+   /* Search dictionary for pairs: */
+   do i = 1 to hbound(dict,1)-1;
+      do j = i+1 to hbound(dict,1);
+         if length(dict(i)) = length(dict(j)) then
+            do;
+               if dict(i) = reverse(dict(j)) then
+                  do;
+                     allocate pair; pair.a = dict(i); pair.b = dict(j);
+                  end;
+            end;
+      end;
+   end;
+
+   put skip list ('There are ' || trim(allocation(pair)) || ' pairs.');
+
+   do while (allocation(pair) > 0);
+      put skip edit (pair) (a, col(20), a); free pair;
+   end;
+end find;