Add c++ support

def.yy

@@ -1,14 +1,17 @@
 %{
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
+#include <cstring>
+#include <cstdio>
+#include <cstdlib>
+#include <FlexLexer.h>
+
 #define INFILE_ERROR 1
 #define OUTFILE_ERROR 2
 
-extern int yylex(void);
-extern void yyerror(const char *s);
-extern int yylineno;
-extern FILE *yyin;
+extern yyFlexLexer lexer;
+
+void yyerror(const char *s);
+int yylex();
+
 %}
 
 %union {
@@ -45,7 +48,7 @@ statement
 
 variable_declaration
     : LET ID COLON INT_TYPE '=' expression SEMICOLON
-        { printf("Deklaracja zmiennej: %s\n", $2); }
+        { printf("Deklaracja zmiennej: %s\n", $2); free($2); }
     ;
 
 expression
@@ -55,11 +58,21 @@ expression
     | expression '/' expression { printf("Wyrazenie z /\n"); }
     | '(' expression ')' { printf("Wyrazenie w nawiasach\n"); }
     | INT_LIT { printf("Literal calkowity: %d\n", $1); }
-    | ID { printf("Identyfikator: %s\n", $1); }
+    | ID { printf("Identyfikator: %s\n", $1); free($1); }
     ;
 
 %%
 
+yyFlexLexer lexer;
+
+int yylex() {
+    return lexer.yylex();
+}
+
+void yyerror(const char *s) {
+    fprintf(stderr, "Blad: %s w linii %d\n", s, lexer.lineno());
+}
+
 int main(int argc, char *argv[]) {
     yyparse();
     return 0;