func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5;   int vl[N + 2], tim, st[N + 2];   int par[N + 2], level[N + 2];   int sp[N + 2][22], n, ed[N + 2];   long long seg[5 * N], lazy[5 * N];   vector<int> adj[N + 2];   void too_lazy(int node, int lo, int hi) {     seg[node] += (lazy[node] * 1LL * (hi - lo + 1));     if (lo != hi) {       lazy[node * 2] += lazy[node];       lazy[node * 2 + 1] += lazy[node];     }     lazy[node] = 0;   }   void upd(int node, int lo, int hi, int lt, int rt, int up) {     too_lazy(node, lo, hi);     if (lo > rt || hi < lt) return;     if (lo >= lt && hi <= rt) {       lazy[node] += up;       too_lazy(node, lo, hi);       return;     }     int md = (lo + hi) / 2;     upd(node * 2, lo, md, lt, rt, up);     upd(node * 2 + 1, md + 1, hi, lt, rt, up);     seg[node] = seg[node * 2] + seg[node * 2 + 1];   }   long long query(int node, int lo, int hi, int lt, int rt) {     too_lazy(node, lo, hi);     if (lo > rt || hi < lt) return 0;     if (lo >= lt && hi <= rt) return seg[node];     int md = (lo + hi) / 2;     long long p1 = query(node * 2, lo, md, lt, rt);     long long p2 = query(node * 2 + 1, md + 1, hi, lt, rt);     return p1 + p2;   }   void dfs(int node, int fro, int h) {     ++tim;     st[node] = tim;     upd(1, 1, n, st[node], st[node], vl[node]);     par[node] = fro;     level[node] = h;     for (auto xx : adj[node]) {       if (xx == fro) continue;       dfs(xx, node, h + 1);     }     ed[node] = tim;   }   void sparse(void) {     memset(sp, -1, sizeof(sp));     for (int i = 1; i <= n; i++) sp[i][0] = par[i];     for (int j = 1; j <= 20; j++) {       for (int i = 1; i <= n; i++) {         if (sp[i][j - 1] == -1) continue;         sp[i][j] = sp[sp[i][j - 1]][j - 1];       }     }   }   int lca(int u, int v) {     if (level[u] < level[v]) swap(u, v);     for (int i = 20; i >= 0; i--) {       if (sp[u][i] == -1) continue;       if (level[sp[u][i]] >= level[v]) u = sp[u][i];     }     if (u == v) return u;     for (int i = 20; i >= 0; i--) {       if (sp[u][i] == -1 || sp[v][i] == -1) continue;       if (sp[u][i] == sp[v][i]) continue;       u = sp[u][i];       v = sp[v][i];     }     return par[u];   }   bool is_in_path(int u, int v, int w) {     if (w == -1) return false;     if (level[w] < level[lca(u, v)]) return false;     if (lca(u, w) == w || lca(v, w) == w)       return true;     else       return false;   }   void update(int u, int v, int rt, int x) {     if (is_in_path(u, v, rt)) {       upd(1, 1, n, st[1], ed[1], x);       return;     }     int lc = lca(u, v);     for (int i = 20; i >= 0; i--) {       if (sp[rt][i] == -1) continue;       if (level[sp[rt][i]] < level[lc]) continue;       if (!is_in_path(u, v, sp[rt][i])) rt = sp[rt][i];     }     if (is_in_path(u, v, par[rt])) {       upd(1, 1, n, st[1], ed[1], x);       upd(1, 1, n, st[rt], ed[rt], -x);     } else       upd(1, 1, n, st[lc], ed[lc], x);   }   void query(int v, int rt) {     if (v == rt) {       cout << query(1, 1, n, 1, n) << endl;       return;     }     for (int i = 20; i >= 0; i--) {       if (sp[rt][i] == -1) continue;       if (level[sp[rt][i]] > level[v]) rt = sp[rt][i];     }     if (par[rt] == v)       cout << query(1, 1, n, 1, n) - query(1, 1, n, st[rt], ed[rt]) << endl;     else       cout << query(1, 1, n, st[v], ed[v]) << endl;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     int q;     cin >> n >> q;     for (int i = 1; i <= n; i++) cin >> vl[i];     for (int i = 1; i < n; i++) {       int u, v;       cin >> u >> v;       adj[u].push_back(v);       adj[v].push_back(u);     }     dfs(1, -1, 1);     sparse();     int rt = 1;     while (q--) {       int ty;       cin >> ty;       if (ty == 1) {         int v;         cin >> v;         rt = v;       } else if (ty == 2) {         int u, v, x;         cin >> u >> v >> x;         update(u, v, rt, x);       } else {         int v;         cin >> v;         query(v, rt);       }     }     return 0;   }   