Base framework for populating tree structure.

1 files changed, 126 insertions, 0 deletions

diff --git a/tree.cpp b/tree.cpp
new file mode 100644
index 0000000..690c964
--- /dev/null
+++ b/tree.cpp
@@ -0,0 +1,126 @@
+
+#include <cstdlib>
+#include <iostream>
+#include <string>
+#include <cassert>
+
+using namespace std;
+
+struct node
+{
+    node* left;
+    node* right;
+    long value;
+
+    node(long _value) : left(NULL), right(NULL), value(_value) {}
+};
+
+void clean_node(node* nd)
+{
+    if (!nd)
+        return;
+
+    clean_node(nd->left);
+    nd->left = NULL;
+    clean_node(nd->right);
+    nd->right = NULL;
+    delete nd;
+}
+
+void clean_tree(node* root)
+{
+    clean_node(root);
+}
+
+void print_node(node* nd)
+{
+    if (!nd)
+        return;
+
+    print_node(nd->left);
+    cout <<  nd->value << " ";
+    print_node(nd->right);
+}
+
+void print_tree(node* root)
+{
+    cout << "tree content: ";
+    print_node(root);
+    cout << endl;
+}
+
+void insert_value(node* root, long value)
+{
+    while (true)
+    {
+        assert(root);
+        if (root->value == value)
+            // duplicates are not allowed.
+            return;
+
+        if (value < root->value)
+        {
+            if (!root->left)
+            {
+                root->left = new node(value);
+                return;
+            }
+
+            root = root->left;
+        }
+        else
+        {
+            assert(value > root->value);
+            if (!root->right)
+            {
+                root->right = new node(value);
+                return;
+            }
+
+            root = root->right;
+        }
+    }
+}
+
+int main()
+{
+    node* root = NULL;
+    while (true)
+    {
+        string val;
+        cin >> val;
+
+        if (val.empty())
+            break;
+
+        if (val == "q" || val == "quit")
+        {
+            cout << "terminating" << endl;
+            break;
+        }
+
+        // End position on successful conversion.
+        const char* end_pos = val.c_str() + val.size();
+
+        char* end_ptr = NULL;
+        long lval = strtol(&val[0], &end_ptr, 10);
+        if (end_pos != end_ptr)
+        {
+            // String didn't get scanned in its entirety. Must have failed.
+            cerr << "invalid integer: " << val << endl;
+            continue;
+        }
+        cout << "input number: " << lval << endl;
+
+        if (!root)
+            root = new node(lval);
+        else
+            insert_value(root, lval);
+
+        print_tree(root);
+    }
+
+    clean_tree(root);
+
+    return EXIT_SUCCESS;
+}