old stuff: algorithms

1 files changed, 118 insertions, 0 deletions

diff --git a/algorithms/binary_tree.cc b/algorithms/binary_tree.cc
new file mode 100644
index 0000000..d912aec
--- /dev/null
+++ b/algorithms/binary_tree.cc
@@ -0,0 +1,118 @@
+#include <iostream>
+
+using std::cout;
+using std::endl;
+
+
+struct Node {
+  int value;
+  Node* pLeft;
+  Node* pRight;
+};
+
+struct Tree {
+  Node* pRoot;
+};
+
+Node*
+new_node(int value)
+{
+  Node* node = new Node;
+  node->value = value;
+  node->pLeft = node->pRight = NULL;
+  return node;
+}
+
+void
+delete_node(Node* pNode)
+{
+  if(pNode->pLeft)
+    delete pNode->pLeft;
+  if(pNode->pRight)
+    delete pNode->pRight;
+  delete pNode;
+}
+
+void
+insert_node(Node* n, Node* i)
+{
+  if(i->value <= n->value) {
+    if(n->pLeft) {
+      insert_node(n->pLeft, i);
+    } else {
+      n->pLeft = i;
+    }
+  } else {
+    if(n->pRight) {
+      insert_node(n->pRight, i);
+    } else {
+      n->pRight = i;
+    }
+  }
+}
+
+void
+insert(Tree& tree, int value)
+{
+  Node *n = new_node(value);
+
+  if(!tree.pRoot) {
+    tree.pRoot = n;
+  } else {
+    if(n->value <= tree.pRoot->value) {
+      if(tree.pRoot->pLeft) {
+        insert_node(tree.pRoot->pLeft, n);
+      } else {
+        tree.pRoot->pLeft = n;
+      }
+    } else {
+      if(tree.pRoot->pRight) {
+        insert_node(tree.pRoot->pRight, n);
+      } else {
+        tree.pRoot->pRight = n;
+      }
+    }
+  }
+}
+
+void
+print_nodes_inorder(Node *n)
+{
+  if(n->pLeft) {
+    print_nodes_inorder(n->pLeft);
+  }
+
+  cout << n->value << endl;
+
+  if(n->pRight) {
+    print_nodes_inorder(n->pRight);
+  }
+}
+
+void
+print_sorted(Tree& tree)
+{
+  Node *n=tree.pRoot;
+
+  print_nodes_inorder(n);
+}
+
+int
+main()
+{
+  Tree tree;
+  tree.pRoot = NULL;
+
+  int feld[10] = {8, 12, 5, 24, 2, 6, 98, 67, 1, 6};
+
+  for(int i = 0; i < 10; ++i)
+    insert(tree, feld[i]);
+
+  print_sorted(tree);
+
+  if(tree.pRoot)
+    delete_node(tree.pRoot);
+
+  return 0;
+}
+