diff --git a/include/Parsodus/grammar.h b/include/Parsodus/grammar.h
index c4b194f..532fc2a 100644
--- a/include/Parsodus/grammar.h
+++ b/include/Parsodus/grammar.h
@@ -32,7 +32,7 @@ namespace pds {
         std::string start; ///< the starting variable
         std::set<std::string> variables; ///< the variables
         std::set<std::string> terminals; ///< the terminals
-        std::map<std::string, std::set<Rule> > rules; ///< the replacement rules
+        std::vector<Rule> rules; ///< the replacement rules
     };
 }
 
diff --git a/src/inputparser.cpp b/src/inputparser.cpp
index 5d9546a..f96bf50 100644
--- a/src/inputparser.cpp
+++ b/src/inputparser.cpp
@@ -72,10 +72,6 @@ namespace pds {
                                 config.grammar.variables.insert(token.content);
                            
                             std::string current_head = token.content;
-                            std::set<Rule> current_rules;
-                            if(config.grammar.rules.count(current_head)) {
-                                current_rules = config.grammar.rules[current_head];
-                            }
                             // Parsing rule
                             token = lex.nextToken();
                             if(token.type != ParsodusLexer::ARROW) 
@@ -96,14 +92,13 @@ namespace pds {
                                         parsing_head = false;
                                     case ParsodusLexer::PIPE:
                                         rule.tail.shrink_to_fit();
-                                        current_rules.insert(rule);
+                                        config.grammar.rules.push_back(rule);
                                         rule.tail.clear();
                                         break;
                                     default:
                                         throw InputParserException("Expecting to find a variable, terminal, pipe or a semicolon, but found '" + token.content + "' instead");
                                 }
                             }
-                            config.grammar.rules[current_head] = current_rules;
                         } else
                             throw InputParserException("Found a variable outside a grammar section: " + token.content);
                         break;
diff --git a/src/main.cpp b/src/main.cpp
index b0f5958..3157d81 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -35,14 +35,13 @@ int main(int argc, char** argv) {
         std::cout << "Terminal: " << a << std::endl;
     for(auto a: config.grammar.variables)
         std::cout << "Variable: " << a << std::endl;
+    std::cout << "Rules: " << std::endl;
     for(auto a: config.grammar.rules) {
-        std::cout << "Starting rule with head: " << a.first << std::endl;
-        for(auto b: a.second) {
-            std::cout << "\tRule with head: " << b.head << std::endl;
-            for(auto c: b.tail) {
-                std::cout << "\t\tFound replacement rule: " << c << std::endl;
-            }
+        std::cout << "\t" << a.head << " -> ";
+        for(auto c: a.tail) {
+            std::cout << c << " ";
         }
+        std::cout << std::endl;
     }
 
 }