func_code_string: #include <bits/stdc++.h>   #ifdef LOCAL   #include  debuger.hpp    #else   #define DUMP(...) 1145141919810   #define CHECK(...) (__VA_ARGS__)   #endif      const int kN = 200000 + 5;   const int INF = 0x3f3f3f3f;   std::vector<int> edges[kN];   int n, q;   int header[kN],dfn[kN],tim,parent[kN],sz[kN];   int depth[kN];   int last[kN];      void get_sz(int u, int fa) {     sz[u] = 1;     for (int v : edges[u]) {       if (v == fa) continue;       depth[v] = depth[u] + 1;       get_sz(v, u);       sz[u] += sz[v];     }   }      void rebuild(int u, int fa, int color) {     dfn[u] = tim ++;     parent[u] = fa;     header[u] = color;     last[color] = u;     int p = -1;     for (int v : edges[u]) {       if (v == fa) continue;       if (p == -1 || sz[v] > sz[p]) {         p = v;       }     }     if (p != -1) {       rebuild(p, u, color);     }     for (int v : edges[u]) {       if (v == fa || v == p) continue;       rebuild(v, u, v);     }   }      int get_lca(int a, int b) {     while (header[a] != header[b]) {       if (dfn[header[a]] < dfn[header[b]]) {         std::swap(a,b);       }       a = parent[header[a]];     }     return dfn[a] < dfn[b] ? a : b;   }      struct SegmentTree {     int mx[kN << 1];        int get_id(int l, int r) const { return l + r | l != r; }     void up(int l, int r) {       if (l != r) {         int mid = l + r >> 1;         mx[get_id(l, r)] = std::max(mx[get_id(l, mid)], mx[get_id(mid + 1, r)]);       }     }     void build(int l, int r) {       mx[get_id(l, r)] = -INF;       if (l != r) {         int mid = l + r >> 1;         build(l, mid);         build(mid + 1, r);       }     }     int query(int L, int R, int l, int r) const {       if (r < L || R < l) return -INF;       if (L <= l && r <= R) return mx[get_id(l, r)];       int mid = l + r >> 1;       return std::max(query(L, R, l, mid), query(L, R, mid + 1, r));     }     void modify(int p, int v, int l, int r) {       if (l == r) {         mx[get_id(l, r)] = v;       } else {         int mid = l + r >> 1;         if (p <= mid) modify(p, v, l, mid);         else modify(p, v, mid + 1, r);         up(l, r);       }     }      } tree[2];  // 0: val-dfn[v], 1: val+dfn[v]      struct Fenwick {     int arr[kN];        void update(int p, int dt) { for (int i = p; i >= 0; i -= ~i & i + 1) arr[i] += dt; }     int query(int p) const { int ret = 0; for (int i = p; i < kN; i += ~i & i + 1) ret += arr[i]; return ret; }        void hld_update(int u, int dt) {       while (u != -1) {         update(dfn[u], dt);         if (dfn[header[u]] > 0) {           update(dfn[header[u]] - 1, -dt);         }         u = parent[header[u]];       }     }   } bit;      const int kLog = 19;   int pjump[kLog][kN];      void init_jump() {     for (int i = 0; i < n; ++i) {       pjump[0][i] = parent[i];     }     for (int i = 0; i + 1 < kLog; ++i) {       for (int u = 0; u < n; ++u) {         pjump[i + 1][u] = pjump[i][u] == -1 ? -1 : pjump[i][pjump[i][u]];       }     }   }      int jump(int u, int d) {     for (int i = 0; i < kLog; ++i) {       if (d >> i & 1) {         u = pjump[i][u];         if (u == -1) return 0;       }     }     return u;   }      std::multiset<std::pair<int, int>> multiset;      std::multiset<int> virtual_sets[kN];      int hld_query(int u, int guard) {     int ret = 0;     int v = u;     int prev_head = -1;     while (v != -1 && dfn[v] >= dfn[guard]) {       int w = header[v];       if (dfn[w] < dfn[guard]) w = guard;       int e = last[header[v]];          if (!virtual_sets[v].empty()) {         int homologous_val = -INF;         if (prev_head != -1) {           int val = tree[1].query(dfn[prev_head], dfn[last[prev_head]], 0, n - 1);           if (val != -INF) {             homologous_val = val - dfn[prev_head] + 1;           }         }         if (homologous_val != *virtual_sets[v].rbegin()) {           ret = std::max(ret, depth[u] - depth[v] + *virtual_sets[v].rbegin());         } else if (virtual_sets[v].size() >= 2) {           ret = std::max(ret, depth[u] - depth[v] + *std::prev(std::prev(virtual_sets[v].end())));         }       }       if (dfn[v] < dfn[e]) {         int val = tree[1].query(dfn[v] + 1, dfn[e], 0, n - 1);         if (val != -INF) {           ret = std::max(ret, val - dfn[v] + depth[u] - depth[v]);         }       }       if (dfn[w] < dfn[v]) {         int val = tree[0].query(dfn[w], dfn[v] - 1, 0, n - 1);         if (val != -INF) {           ret = std::max(ret, val + dfn[v] + depth[u] - depth[v]);         }       }       DUMP(v, ret);       prev_head = header[v];       v = parent[header[v]];     }     return ret;   }      #define ERASE_ONE(set, elem) (set).erase((set).find(elem))      void hld_insert(int u) {     std::vector<int> stack;     for (int v = u; v != -1; v = parent[header[v]]) {       stack.emplace_back(v);     }     for (int i = (int)stack.size() - 1; i >= 0; --i) {       int x = stack[i];       int h = header[x];       if (parent[h] != -1) {         int val = tree[1].query(dfn[h], dfn[last[h]], 0, n - 1);         if (val != -INF) {           ERASE_ONE(virtual_sets[parent[h]], val - dfn[h] + 1);         }       }     }     virtual_sets[u].emplace(0);     for (int x : stack) {       int val = *virtual_sets[x].rbegin();       tree[0].modify(dfn[x], val - dfn[x], 0, n - 1);       tree[1].modify(dfn[x], val + dfn[x], 0, n - 1);       int h = header[x];       if (parent[h] != -1) {         int val = tree[1].query(dfn[h], dfn[last[h]], 0, n - 1);         if (val != -INF) {           virtual_sets[parent[h]].emplace(val - dfn[h] + 1);         }       }     }   }      void hld_remove(int u) {     std::vector<int> stack;     for (int v = u; v != -1; v = parent[header[v]]) {       stack.emplace_back(v);     }     for (int i = (int)stack.size() - 1; i >= 0; --i) {       int x = stack[i];       int h = header[x];       if (parent[h] != -1) {         int val = tree[1].query(dfn[h], dfn[last[h]], 0, n - 1);         if (val != -INF) {           ERASE_ONE(virtual_sets[parent[h]], val - dfn[h] + 1);         }       }     }     ERASE_ONE(virtual_sets[u], 0);     for (int x : stack) {       if (!virtual_sets[x].empty()) {         int val = *virtual_sets[x].rbegin();         tree[0].modify(dfn[x], val - dfn[x], 0, n - 1);         tree[1].modify(dfn[x], val + dfn[x], 0, n - 1);       } else {         tree[0].modify(dfn[x], -INF, 0, n - 1);         tree[1].modify(dfn[x], -INF, 0, n - 1);       }       int h = header[x];       if (parent[h] != -1) {         int val = tree[1].query(dfn[h], dfn[last[h]], 0, n - 1);         if (val != -INF) {           virtual_sets[parent[h]].emplace(val - dfn[h] + 1);         }       }     }   }      int main() {     scanf( %d%d , &n, &q);     for (int i = 0; i < n - 1; ++i) {       int a, b;       scanf( %d%d , &a, &b); --a; --b;       edges[a].emplace_back(b);       edges[b].emplace_back(a);     }     get_sz(0, -1);     rebuild(0, -1, 0);     tree[0].build(0, n - 1);     tree[1].build(0, n - 1);     init_jump();     while (q--) {       int op;       scanf( %d , &op);       if (op == 1) {         int u, v;         scanf( %d%d , &u, &v); --u; --v;         int lca = get_lca(u, v);         bit.hld_update(u, 1);         bit.hld_update(v, 1);         bit.hld_update(lca, -1);         multiset.emplace(depth[lca], lca);         hld_insert(lca);       } else if (op == 2) {         int u, v;         scanf( %d%d , &u, &v); --u; --v;         int lca = get_lca(u, v);         bit.hld_update(u, -1);         bit.hld_update(v, -1);         bit.hld_update(lca, 1);         ERASE_ONE(multiset, std::make_pair(depth[lca], lca));         hld_remove(lca);       } else {         int d;         scanf( %d , &d);         CHECK(!multiset.empty());         int v = multiset.rbegin()->second;         int guard = jump(v, d + d);         if (bit.query(dfn[guard]) != bit.query(dfn[0])) {           puts( No );           continue;         }         puts(hld_query(v, guard) <= d + d ?  Yes  :  No );       }     }   }   