dear friend, here is the error i get after running my codes like this: simmat.pl 1.txt 2.txt res

Scalar found where operator expected at simmat.pl line 43, near ")
        $sim"
        (Missing operator before $sim?)
Global symbol "@words" requires explicit package name at simmat.pl lin
+e 36.
Global symbol "@words" requires explicit package name at simmat.pl lin
+e 40.
Global symbol "@words" requires explicit package name at simmat.pl lin
+e 41.
Global symbol "@sim" requires explicit package name at simmat.pl line 
+42.
Global symbol "@words" requires explicit package name at simmat.pl lin
+e 42.
Global symbol "@words" requires explicit package name at simmat.pl lin
+e 42.
syntax error at simmat.pl line 43, near ")
        $sim"
Global symbol "@sim" requires explicit package name at simmat.pl line 
+43.
Global symbol "@sim" requires explicit package name at simmat.pl line 
+43.
Global symbol "@sim" requires explicit package name at simmat.pl line 
+57.
Execution of simmat.pl aborted due to compilation errors.
[download]

any idea where is the error from?