creat tree O(n²) -> O(nlog(n))

src/node.rs

@@ -1,3 +1,4 @@
+use std::collections::BTreeSet;
 use std::collections::HashMap;
 use std::collections::VecDeque;
 
@@ -8,7 +9,25 @@ pub struct Node {
     pub n: i32,
     pub path: String,
 }
+impl PartialEq for Node {
+    fn eq(&self, other: &Self) -> bool {
+        self.n == other.n
+    }
+}
 
+impl Eq for Node {}
+
+impl PartialOrd for Node {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl Ord for Node {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.n.cmp(&other.n)
+    }
+}
 impl Node {
     pub fn new() -> Self {
         Node {
@@ -65,13 +84,19 @@ pub fn tree_to_map(root: &mut Node, char_to_bin: bool) -> HashMap<String, String
 
 pub fn create_tree(mut nodes: Vec<Node>) -> Node {
     while nodes.len() > 1 {
-        nodes.sort_by_key(|node| node.n);
+        //nodes.sort_by_key(|node| node.n);
         let mut new_root = Node::new();
         let l = nodes.remove(0);
         let r = nodes.remove(0);
         new_root.set_counter(l.n + r.n);
         new_root.insert(l, r);
-        nodes.push(new_root);
+        //nodes.push(new_root);
+        match nodes.binary_search(&new_root) {
+            Ok(_) => {}
+            Err(pos) => {
+                nodes.insert(pos, new_root);
+            }
+        }
     }
     nodes.pop().unwrap()
 }