From 237c620647db2e6684f144b90dd8d96a4c5ca60f Mon Sep 17 00:00:00 2001
From: wisdompeak <guan.huifeng@gmail.com>
Date: Sun, 15 Jun 2025 01:16:31 -0700
Subject: [PATCH 1/2] Create binary_lift.cpp

---
 Template/Binary_Lift/binary_lift.cpp | 74 ++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 Template/Binary_Lift/binary_lift.cpp

diff --git a/Template/Binary_Lift/binary_lift.cpp b/Template/Binary_Lift/binary_lift.cpp
new file mode 100644
index 000000000..7f6186fff
--- /dev/null
+++ b/Template/Binary_Lift/binary_lift.cpp
@@ -0,0 +1,74 @@
+using ll = long long;
+const int MAXN = 100000;
+const int LOGN = 17;
+class Solution {
+public:    
+    vector<pair<int,int>> adj[MAXN];
+    int up[MAXN][LOGN+1];
+    int depth[MAXN];
+    ll distRoot[MAXN];
+
+    void dfs(int cur, int parent)
+    {
+        up[cur][0] = parent;
+        for(auto &[v,w]: adj[cur])
+        {
+            if(v == parent) continue;
+            depth[v] = depth[cur] + 1;
+            distRoot[v] = distRoot[cur] + w;
+            dfs(v, cur);
+        }
+    }
+
+    int lca(int a, int b)
+    {
+        if(depth[a] < depth[b]) swap(a,b);
+        int diff = depth[a] - depth[b];
+        for(int k = 0; k <= LOGN; k++){
+            if(diff & (1<<k)) a = up[a][k];
+        }
+        if(a == b) return a;
+        for(int k = LOGN; k >= 0; k--){
+            if(up[a][k] != up[b][k]){
+                a = up[a][k];
+                b = up[b][k];
+            }
+        }
+        return up[a][0];
+    }
+
+    ll dist(int a, int b)
+    {
+        int c = lca(a,b);
+        return distRoot[a] + distRoot[b] - 2*distRoot[c];
+    }
+
+    ll stepUp(int u, int k) {        
+        for (int i=LOGN; i>=0; i--) {
+            if ((k>>i)&1) {
+                u = up[u][i];
+            }
+        }
+        return u;
+    }
+
+    void solve(vector<vector<int>>& edges) {
+        for (auto& edge: edges)
+        {
+            int u = edge[0], v = edge[1], w = edge[2];
+            adj[u].push_back({v,w});
+            adj[v].push_back({u,w});
+        }
+        
+        depth[0] = 0;
+        distRoot[0] = 0;
+        dfs(0, 0);
+
+        for(int k = 1; k <= LOGN; k++) {
+            for(int v = 0; v < n; v++) {
+                up[v][k] = up[up[v][k-1]][k-1];
+            }
+        }
+
+        // Solve your problem.
+    }

From cbf27c08f43d6e3438343ce106a1e539c044250e Mon Sep 17 00:00:00 2001
From: wisdompeak <guan.huifeng@gmail.com>
Date: Sun, 15 Jun 2025 01:17:25 -0700
Subject: [PATCH 2/2] Update Readme.md

---
 Readme.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Readme.md b/Readme.md
index 28e1d55b4..0e1dda6f8 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1697,6 +1697,7 @@
 [Graph](https://github.com/wisdompeak/LeetCode/tree/master/Template/Graph)  
 [Bit_Manipulation](https://github.com/wisdompeak/LeetCode/tree/master/Template/Bit_manipulation)  
 [RB_Tree](https://github.com/wisdompeak/LeetCode/tree/master/Template/RB_Tree)  
+[Binary_Lift](https://github.com/wisdompeak/LeetCode/tree/master/Template/Binary_Lift)
 [二维子矩阵求和](https://github.com/wisdompeak/LeetCode/tree/master/Template/Sub_Rect_Sum_2D)    
 [二维差分数组](https://github.com/wisdompeak/LeetCode/tree/master/Template/Diff_Array_2D)    
 [CPP_LANG](https://github.com/wisdompeak/LeetCode/tree/master/Template/CPP_LANG)