Added << operators for every tree header

src/classes/tree/avl_tree.h

@@ -194,6 +194,24 @@ template <typename T> class avl_tree {
     tree_visualization::visualize(__generated);
   }
 
+  /**
+   * @brief operator << for avl_tree class
+   */
+  friend ostream & operator << (ostream &out, avl_tree<T> &t){
+    std::vector<std::vector<T> > order = t.level_order();
+    for(std::vector<T> & x : order){
+      for(size_t i = 0; i < x.size(); i++){
+        if(i != x.size() - 1){
+          out << x[i] << ", ";
+        }
+        else{
+          out << x[i] << '\n';
+        }
+      }
+    }
+    return out;
+  }
+
 private:
   /**
    *@brief Struct for the node type pointer.

src/classes/tree/bst.h

@@ -192,6 +192,25 @@ template <typename T> class bst {
     tree_visualization::visualize(__generated);
   }
 
+
+  /**
+   * @brief operator << for bst class
+   */
+  friend ostream & operator << (ostream &out, bst<T> &t){
+    std::vector<std::vector<T> > order = t.level_order();
+    for(std::vector<T> & x : order){
+      for(size_t i = 0; i < x.size(); i++){
+        if(i != x.size() - 1){
+          out << x[i] << ", ";
+        }
+        else{
+          out << x[i] << '\n';
+        }
+      }
+    }
+    return out;
+  }
+
 private:
   /**
    *@brief Struct for the node type pointer.

src/classes/tree/interval_tree.h

@@ -210,19 +210,20 @@ template <typename T> class interval_tree {
   }
 
   /**
-   *@brief << operator for interval_tree class.
+   * @brief operator << for interval tree class
    */
-  friend std::ostream &operator<<(std::ostream &out, interval_tree<T> &t) {
-    if (!t.root) {
-      out << "";
-      return out;
-    }
-    out << '"';
-    std::vector<std::pair<T, T>> __inorder = t.inorder();
-    for (auto &x : __inorder) {
-      out << '"' << x.first << ' ' << x.second << '"' << " ";
+  friend ostream & operator << (ostream &out, interval_tree<T> &t){
+    std::vector<std::vector<std::pair<T, T> > > order = t.level_order();
+    for(std::vector<std::pair<T, T> > & x : order){
+      for(size_t i = 0; i < x.size(); i++){
+        if(i != x.size() - 1){
+          out << '[' << x[i].first << "," << x[i].second << ']' << ", ";
+        }
+        else{
+          out << '[' << x[i].first << "," << x[i].second << ']' << '\n';
+        }
+      }
     }
-    out << '"';
     return out;
   }
 

src/classes/tree/splay_tree.h

@@ -205,6 +205,24 @@ template <typename T> class splay_tree {
     tree_visualization::visualize(__generated);
   }
 
+  /**
+   * @brief operator << for splay tree class
+   */
+  friend ostream & operator << (ostream &out, splay_tree<T> &t){
+    std::vector<std::vector<T> > order = t.level_order();
+    for(std::vector<T> & x : order){
+      for(size_t i = 0; i < x.size(); i++){
+        if(i != x.size() - 1){
+          out << x[i] << ", ";
+        }
+        else{
+          out << x[i] << '\n';
+        }
+      }
+    }
+    return out;
+  }
+
 private:
   std::shared_ptr<node> rrotate(std::shared_ptr<node> _node) {
     std::shared_ptr<node> y = _node->left;
@@ -450,4 +468,4 @@ template <typename T> class splay_tree<T>::Iterator {
   T operator*() { return elements[index]; }
 };
 
-#endif
+#endif

src/classes/tree/tree.h

@@ -3,6 +3,7 @@
 #define TREE_H
 
 #ifdef __cplusplus
+#include "../../visualization/tree_visual/tree_visualization.h"
 #include <functional>
 #include <iostream>
 #include <queue>
@@ -178,6 +179,24 @@ template <typename T> class tree {
     return path;
   }
 
+  /**
+   * @brief operator << for bst class
+   */
+  friend ostream & operator << (ostream &out, tree<T> &t){
+    std::vector<std::vector<T> > order = t.level_order();
+    for(std::vector<T> & x : order){
+      for(size_t i = 0; i < x.size(); i++){
+        if(i != x.size() - 1){
+          out << x[i] << ", ";
+        }
+        else{
+          out << x[i] << '\n';
+        }
+      }
+    }
+    return out;
+  }
+
 private:
   void __inorder(std::function<void(std::shared_ptr<node>)> callback,
                  std::shared_ptr<node> root) {