examples: fix c/calc

[Akim Demaille]

commit 15e57d910802f6823dd2abf0321562b6b1209087
Author: Akim Demaille <akim.demai...@gmail.com>
Date:   Wed Feb 19 14:58:39 2020 +0100

    examples: fix c/calc
    
    * examples/c/calc/calc.y: Remove experiment traces.

diff --git a/examples/c/calc/calc.y b/examples/c/calc/calc.y
index 1a6980fe..7757648d 100644
--- a/examples/c/calc/calc.y
+++ b/examples/c/calc/calc.y
@@ -34,7 +34,6 @@ input:
 
 line:
   '\n'
-  | 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' 'a' { printf 
("a\n"); }
 | expr '\n'  { printf ("%.10g\n", $1); }
 | error '\n' { yyerrok; }
 ;