diff --git a/lexer.c b/lexer.c
index e566f68..d96b605 100644
--- a/lexer.c
+++ b/lexer.c
@@ -9,9 +9,13 @@ typedef struct Exploration Exploration;
 enum opcode {
     STRING,
     AND,
+    OR,
     STAR,
     PLUS,
-    QMARK
+    CLASS,
+    QUESTION_MARK,
+    EXCLAMATION_MARK,
+    DOT
 };
 struct Exploration
 {
@@ -27,27 +31,34 @@ Exploration *mkExploration(char *text)
     return exploration;
 }
 
-char advance(Exploration *exploration)
+void advance(Exploration *exploration, int add)
 {
-    return exploration->text[exploration->position++];
+    exploration->position+= add;
 }
 
-int endExploration(Exploration *exploration)
-{
-    if (exploration->position >= strlen(exploration->text))
-    {
-        return 1;
-    } else
-    {
-        return 0;
+int atEnd(Exploration *exploration) {
+    return exploration->text[exploration->position] == 0;
     }
-}
 
 void setPosition(Exploration *exploration, int position)
 {
     exploration->position= position;
 }
 
+int getPosition(Exploration *exploration) {
+    return exploration->position;
+}
+
+int currentChar(Exploration *exploration)
+{
+    return exploration->text[exploration->position];
+}
+
+char *currentText(Exploration *exploration)
+{
+    return exploration->text + exploration->position;
+}
+
 
 struct Node
 {
@@ -97,67 +108,113 @@ Node *mkPlus(Node *child)
     return node;
 }
 
-Node *mkQmark(Node *child)
+Node *mkOr(Node *node1, Node *node2)
+{
+    Node *node= mkNode(OR);
+    node->children[0]= node1;
+    node->children[1]= node2;
+    return node;
+}
+
+Node *mkClass(char* str)
+{
+    Node *node= mkNode(CLASS);
+    node->stringValue= str;
+    return node;
+}
+
+Node *mkQuestionMark(Node *child)
+{
+    Node *node= mkNode(QUESTION_MARK);
+    node->children[0]= child;
+    return node;
+}
+
+Node *mkExclamationMark(Node *child)
 {
-    Node *node= mkNode(QMARK);
+    Node *node= mkNode(EXCLAMATION_MARK);
     node->children[0]= child;
     return node;
 }
 
+Node *mkDot()
+{
+    Node *node= mkNode(DOT);
+    return node;
+}
+
+
+
+
 int execute(Node *node, Exploration *in)
 {
     switch (node->type) {
       case STRING: {
-      for (int i=0; i < strlen(node->stringValue);i++)
-      {
-          if (advance(in) != node->stringValue[i])
-          {
-              return 0;
-          }
-      }
-      if (endExploration(in)==1)
-      {
-          return 1;
-      } else
-      {
-          return -1;
+      int length= strlen(node->stringValue);
+      if (strncmp(currentText(in), node->stringValue, length)) {
+        return 0;
       }
+      advance(in, length);
+      return 1;
       }
       case AND: {
-      if (execute(node->children[0], in) == 0) //si il y a eu une erreur
+      int pos= getPosition(in);
+      if (!execute(node->children[0], in)) //si il y a eu une erreur
       {
           return 0;
-      } else //si ça s'est bien passé
-      {
-          return execute(node->children[1], in);
+      } //si ça s'est bien passé
+      if (!execute(node->children[1], in)) {
+          setPosition(in, pos);
+          return 0;
+      }
+      return 1;
+      }
+      case OR: {
+      if (execute(node->children[0], in)) {
+          return 1;
       }
+      return execute(node->children[1], in);
       }
       case STAR: {
-          if(execute(node->children[0], in) == 1){
-              execute(node->children[0], in);
-          }
-          else return 1;
+      while (execute(node->children[0], in));
+      return 1;
       }
       case PLUS: {
-          if(execute(node->children[0],in)==0){
-              return 0;
-          }
-          else{
-            while(execute(node->children[0], in) == 1){
-                       
-                            execute(node->children[0], in);
-                        
-                    }
-                return 1;
-          
-          }
-         
-      }
-        case QMARK: {
-            // 0 ou 1
-            if(execute(node->children[0], in)==1) return execute(node->children[0], in);
-            return 1;
-        }
+      if (!execute(node->children[0], in)) {
+        return 0;
+      }
+      while (execute(node->children[0], in));
+      return 1;
+      }
+      case CLASS: {
+      if (!currentChar(in)) {
+        return 0;
+      }
+      if (strchr(node->stringValue, currentChar(in))) {
+        advance(in, 1);
+        return 1;
+      }
+      return 0;
+      }
+      case QUESTION_MARK: {
+      execute(node->children[0], in);
+      return 1;
+      }
+      case EXCLAMATION_MARK: {
+      int pos= getPosition(in);
+      if (!execute(node->children[0], in)) {
+        return 1;
+      }
+      setPosition(in, pos);
+      return 0;
+      }
+      case DOT: {
+      if (atEnd(in)) {
+        return 0;
+      }
+      advance(in, 1);
+      return 1;
+      }
     }
     printf("this cannot happen\n");
     abort();
@@ -166,11 +223,10 @@ int execute(Node *node, Exploration *in)
 
 int main(int argc, char **argv)
 {
-    Exploration *in= mkExploration("acc");
+    Exploration *in= mkExploration("aabbcc");
 
     /*Node *program=
 	mkString("aabbcc");
-
     Node *program=
 	mkAnd(mkString("aab"),
 	      mkString("bcc"));*/
@@ -180,37 +236,22 @@ int main(int argc, char **argv)
 	      mkAnd(mkString("bb"),
 		    mkString("cc")));*/
 
-  /*  Node *program=
-        mkAnd( mkString("aabbcc"),   
-            mkAnd(mkStar(mkString("c")),       // "a"*"b"*"c"*
+    /*Node *program=
+            mkOr(mkPlus(mkString("a")),       // "a"*"b"*"c"*
                 mkAnd(mkStar(mkString("b")),
-                mkStar(mkString("c")))));
-*/
-    Node *program= 
-            mkAnd(mkQmark(mkString("a")),       // "a"*"b"*"c"*
-                mkAnd(mkQmark(mkString("b")),
-                mkPlus(mkString("c"))));
-
-    if (execute(program, in)<=0)
-    {
-        printf("no match\n");
-    } else
-    {
-        printf("match\n");
-    }// 0 => no match, 1 => match
-
+                mkStar(mkString("c"))));*/
 
 
+    Node *program= mkStar(mkClass("abc"));
 
-    /*Input *in1= mkInput("hello");
-    Input *in2= mkInput("world");
-    Input *in3= mkInput("hello world");
-
-    Node *program=
-	      mkOr(mkString("hello"),       // "hello" | "world"
-		   mkString("world"));
 
-    printf("%i\n", execute(program, in));  // 0 => no match, 1 => match*/
+    if (!execute(program, in) || !atEnd(in))
+    {
+        printf("no match, current position : %i\n", getPosition(in));
+    } else
+    {
+        printf("match, current position : %i\n", getPosition(in));
+    }// 0 => no match, 1 => match