diff --git a/src/extstring.c b/src/extstring.c
index d4de042..f2fb558 100644
--- a/src/extstring.c
+++ b/src/extstring.c
@@ -14,9 +14,9 @@ void es_addsymbol(struct Extstring* string, char symbol) {
 }
 
 int es_size(struct Extstring* string) {
-	int size;
+	int size = 0;
 	struct Extstring* ptr = string;
-	for (size = 0; ptr != NULL; size++) {
+	for (; ptr != NULL; size++) {
 		ptr = ptr->next;
 	}
 	return size;
@@ -37,19 +37,17 @@ void es_free(struct Extstring* string) {
 	free(ptr);
 }
 
-struct SString* es_tostring(struct Extstring* string) {
+char* es_tostring(struct Extstring* string) {
 	struct Extstring* ptr = string;
 	int size = es_size(string) + 1;
-	struct SString* sstring = malloc(sizeof(struct SString));
-	sstring->string = malloc(size);
-	sstring->size = size;
+	char* cstring = malloc(size);
 	for (int i = 0; i != size; i++) {
 		if (ptr != NULL) {
-			sstring->string[i] = ptr->symbol;
+			cstring[i] = ptr->symbol;
 			ptr = ptr->next;
 		}
 		else
-			sstring->string[i] = 0;
+			cstring[i] = 0;
 	}
-	return sstring;
+	return cstring;
 }
diff --git a/src/extstring.h b/src/extstring.h
index 623ef45..b4d7a16 100644
--- a/src/extstring.h
+++ b/src/extstring.h
@@ -3,12 +3,7 @@ struct Extstring {
 	struct Extstring* next;
 };
 
-struct SString {
-	int size;
-	char* string;
-};
-
 void es_addsymbol(struct Extstring* string, char symbol);
 int es_size(struct Extstring* string);
 void es_free(struct Extstring* string);
-struct SString* es_tostring(struct Extstring* string);
+char* es_tostring(struct Extstring* string);
diff --git a/src/main.c b/src/main.c
index 8e53609..2822ade 100644
--- a/src/main.c
+++ b/src/main.c
@@ -15,10 +15,13 @@ int main(int argc, char *argv[]) {
 	}
 	file = fopen(argv[1],"r");
 	struct SyntaxElement* code = parse(file);
+	fclose(file);
 	if (code == NULL) {
 		fprintf(stderr, "Error during parsing.\n");
 		return 1;
 	}
 	printtree(code,0);
+	se_free(code);
+	code = NULL;
 	return 0;
 }
diff --git a/src/parser.c b/src/parser.c
index 30beed9..c9d2014 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -28,6 +28,27 @@ struct SyntaxElement* se_next(struct SyntaxElement* syntaxelement) {
 	return syntaxelement->next;
 }
 
+void se_free(struct SyntaxElement* syntaxtree) {
+	switch (syntaxtree->type) {
+		case NONE:
+			free(syntaxtree);
+			return;
+		case TREE:
+		case TOPTREE:
+			if (syntaxtree->content != NULL) {
+				se_free((struct SyntaxElement*)syntaxtree->content);
+			}
+			break;
+		default:
+			free(syntaxtree->content);
+			break;
+	}
+	if (syntaxtree->next != NULL) {
+		se_free(syntaxtree->next);
+	}
+	free(syntaxtree);
+}
+
 void se_clean(struct SyntaxElement* syntaxtree) {
 	if (syntaxtree->next != NULL) {
 		switch (syntaxtree->next->type) {
@@ -80,7 +101,7 @@ struct SyntaxElement* parse(FILE* file) {
 				}
 				instring = false;
 				syntaxtree->type = STRING;
-				char* sstring = es_tostring(string)->string;
+				char* sstring = es_tostring(string);
 				syntaxtree->content = sstring;
 				es_free(string);
 				string = NULL;
@@ -99,7 +120,7 @@ struct SyntaxElement* parse(FILE* file) {
 			if (isspace(symbol) || symbol == '(' || symbol == ')') {
 				intoken = false;
 				syntaxtree->type = TOKEN;
-				char* sstring = es_tostring(token)->string;
+				char* sstring = es_tostring(token);
 				syntaxtree->content = sstring;
 				es_free(token);
 				token = NULL;
diff --git a/src/parser.h b/src/parser.h
index ac60f55..55cb73f 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -2,6 +2,11 @@
 
 #ifndef PARSER_H
 #define PARSER_H
+struct SyntaxElement* se_init(void);
+struct SyntaxElement* se_bottom(struct SyntaxElement* syntaxelement);
+struct SyntaxElement* se_next(struct SyntaxElement* syntaxelement);
+void se_free(struct SyntaxElement* syntaxtree);
+
 enum SyntaxElementType {
 	TOPTREE,
 	TREE,