diff --git a/ps3/src/tree.c b/ps3/src/tree.c
index ae3561b..9599fa2 100644
--- a/ps3/src/tree.c
+++ b/ps3/src/tree.c
@@ -148,7 +148,7 @@ static node_t* convert_operator(node_t* node)
     node_finalize(node);
     node = converted_op;
   } else {
-    printf("convert_operator: found op `%s`\n", node->data.operator);
+    /* printf("convert_operator: found op `%s`\n", node->data.operator); */
   }
   return node;
 }
@@ -157,8 +157,10 @@ static node_t* convert_operator(node_t* node)
 static node_t* constant_fold_operator(node_t* node)
 {
   assert(node->type == OPERATOR);
+  bool cont = 1;
   for (int i = 0; i < node->n_children; i++)
-    assert(node->children[i]->type == NUMBER_LITERAL);
+    cont &= node->children[i]->type == NUMBER_LITERAL;
+  if (!cont) return node;
   
   node_t *a, *b, *c, *result;
   if (node->n_children == 1) {
@@ -296,7 +298,7 @@ static node_t* simplify_subtree(node_t* node)
 
   switch (node->type) {
   case OPERATOR:
-    return convert_operator(node);
+    return constant_fold_operator(convert_operator(node));
   case PRINTLN_STATEMENT:
     return simplify_println_statement(node);
   case BLOCK: