func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5 + 10;   const int level = 20;   vector<int> adj[N];   bool checked[N];   int parent[N];   int sz[N];   int centroid;   int sparse[N][level];   int depth[N];   void subtree(int cur, int prev) {     sz[cur] = 1;     for (auto &child : adj[cur]) {       if (child != prev and !checked[child]) {         subtree(child, cur);         sz[cur] += sz[child];       }     }   }   void decompose(int cur, int prev, int total_size) {     for (auto &child : adj[cur]) {       if (child != prev and !checked[child]) {         decompose(child, cur, total_size);       }     }     if (centroid != -1) {       return;     }     if (2 * sz[cur] >= total_size) {       centroid = cur;       return;     }   }   int get_centroid(int cur) {     subtree(cur, 0);     centroid = -1;     decompose(cur, 0, sz[cur]);     return centroid;   }   void dfs(int cur, int prev) {     int root = get_centroid(cur);     parent[root] = prev;     checked[root] = true;     for (auto &child : adj[root]) {       if (!checked[child]) {         dfs(child, root);       }     }   }   void dfs_sparse(int cur, int prev) {     sparse[cur][0] = prev;     for (auto &child : adj[cur]) {       if (child != prev) {         depth[child] = depth[cur] + 1;         dfs_sparse(child, cur);       }     }   }   void solve() {     int n, m;     cin >> n >> m;     for (int i = 1; i <= n - 1; i++) {       int x, y;       cin >> x >> y;       adj[x].push_back(y);       adj[y].push_back(x);     }     dfs(1, 0);     dfs_sparse(1, -1);     for (int l = 1; l < level; l++) {       for (int node = 1; node <= n; node++) {         if (sparse[node][l - 1] != -1) {           sparse[node][l] = sparse[sparse[node][l - 1]][l - 1];         }       }     }     auto lca = [&](int u, int v) -> int {       if (depth[v] < depth[u]) {         swap(u, v);       }       int diff = depth[v] - depth[u];       for (int i = 0; i < level; i++) {         if ((diff >> i) & 1) {           v = sparse[v][i];         }       }       if (u == v) {         return u;       }       for (int i = level - 1; i >= 0; i--) {         if (sparse[u][i] != sparse[v][i]) {           u = sparse[u][i];           v = sparse[v][i];         }       }       return sparse[u][0];     };     auto get_dist = [&](int x, int y) {       int lc = lca(x, y);       return depth[x] + depth[y] - 2 * depth[lc];     };     vector<int> dist(n + 1, n);     int node = 1;     for (int i = node; i; i = parent[i]) {       dist[i] = get_dist(i, node);     }     for (int i = 1; i <= m; i++) {       int type, node;       cin >> type >> node;       if (type == 1) {         for (int i = node; i; i = parent[i]) {           dist[i] = min(dist[i], get_dist(i, node));         }       } else {         int ans = n;         for (int i = node; i; i = parent[i]) {           ans = min(ans, get_dist(i, node) + dist[i]);         }         cout << (dist[node] = ans) <<   n ;       }     }   }   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     solve();   }   