1 files changed, 29 insertions, 20 deletions

diff --git a/parser.cpp b/parser.cpp
index e1595f3..04f6a50 100644
--- a/parser.cpp
+++ b/parser.cpp
@@ -8,31 +8,31 @@ using std::string, std::stoi;
 
 // De haber habido un error vaciaremos la pila de expresiones.
 void Parser::panic() {
-  for(auto ptr = tree_stack.begin(); ptr != tree_stack.end(); ++ptr)
+  for(auto ptr = tree_queue.begin(); ptr != tree_queue.end(); ++ptr)
     delete *ptr;
 
   throw ParserException("Sintaxis incorrecta.");
 }
 
-Expression *Parser::popStack() {
-  Expression *val = tree_stack.back();
-  tree_stack.pop_back();
+Expression *Parser::popQueue() {
+  Expression *val = tree_queue.front();
+  tree_queue.pop_front();
 
   return val;
 }
 
-Expression *Parser::newTree(token_type type) {
+Expression *Parser::newTree(token_type type, Expression *left, Expression *right) {
   switch(type) {
   case sum:
-    return new AddExpression(popStack(), popStack());
+    return new AddExpression(left, right);
   case substraction:
-    return new SubExpression(popStack(), popStack());
+    return new SubExpression(left, right);
   case multiplication:
-    return new MultiplicationExpression(popStack(), popStack());
+    return new MultiplicationExpression(left, right);
   case division:
-    return new DivisionExpression(popStack(), popStack());
+    return new DivisionExpression(left, right);
   default: // Potencia.
-    return new PowerExpression(popStack(), popStack());
+    return new PowerExpression(left, right);
   }
 }
 
@@ -55,7 +55,7 @@ Expression *Parser::parse(string expr) {
   if(tokenizer.getCurrentToken().type != nil)
     panic();
 
-  return popStack();
+  return popQueue();
 }
 
 void Parser::parseExpr() {
@@ -65,6 +65,7 @@ void Parser::parseExpr() {
 
 void Parser::parsePrimeExpr() {
   token_type current;
+  Expression *left, *right;
   
   if(tokenizer.getCurrentToken().type == sum
      || tokenizer.getCurrentToken().type == substraction) {
@@ -74,8 +75,10 @@ void Parser::parsePrimeExpr() {
     if(checkToken())
       panic();
 
+    left = popQueue();
     parseTerm();
-    tree_stack.push_back(newTree(current));
+    right = popQueue();
+    tree_queue.push_back(newTree(current, left, right));
     parsePrimeExpr();
   }
 }
@@ -87,6 +90,7 @@ void Parser::parseTerm() {
 
 void Parser::parsePrimeTerm() {
   token_type current;
+  Expression *left, *right;
   
   if(tokenizer.getCurrentToken().type == multiplication
      || tokenizer.getCurrentToken().type == division) {
@@ -96,8 +100,10 @@ void Parser::parsePrimeTerm() {
     if(checkToken())
       panic();
 
+    left = popQueue();
     parsePower();
-    tree_stack.push_back(newTree(current));
+    right = popQueue();
+    tree_queue.push_back(newTree(current, left, right));
     parsePrimeTerm();
   }
 }
@@ -108,16 +114,19 @@ void Parser::parsePower() {
 }
 
 void Parser::parsePrimePower() {
+  Expression *left, *right;
+  
   if(tokenizer.getCurrentToken().type == power) {
     tokenizer.nextToken();
 
     if(tokenizer.getCurrentToken().type != number)
       panic();
 
-    tree_stack.push_back(new Literal(stoi(tokenizer.getCurrentToken().value)));
+    left = popQueue();
+    right = new Literal(stoi(tokenizer.getCurrentToken().value));
     tokenizer.nextToken();
-
-    tree_stack.push_back(newTree(power));
+    
+    tree_queue.push_back(newTree(power, left, right));
     parsePrimePower();
   }
 }
@@ -130,7 +139,7 @@ void Parser::parseFactor() {
     tokenizer.nextToken();
     
     parseExpr();
-    tree_stack.push_back(new NegationExpression(popStack()));
+    tree_queue.push_back(new NegationExpression(popQueue()));
     
     break;
   case left_parens:
@@ -170,7 +179,7 @@ void Parser::parseFactor() {
       panic();
     
     tokenizer.nextToken();
-    tree_stack.push_back(new Function(popStack(), name));
+    tree_queue.push_back(new Function(popQueue(), name));
     
     break;
   case variable:
@@ -181,12 +190,12 @@ void Parser::parseFactor() {
     else
       panic(); // Se introdujeron dos variables en la expresión.
     
-    tree_stack.push_back(new Variable(tokenizer.getCurrentToken().value[0]));
+    tree_queue.push_back(new Variable(tokenizer.getCurrentToken().value[0]));
     tokenizer.nextToken();
   
     break;
   case number:
-    tree_stack.push_back(new Literal(stoi(tokenizer.getCurrentToken().value)));
+    tree_queue.push_back(new Literal(stoi(tokenizer.getCurrentToken().value)));
     tokenizer.nextToken();
 
     break;