func_code_string: #include <bits/stdc++.h>   using namespace std;   vector<int> adj[100005];   struct Tree {     vector<vector<int> > anc;     vector<vector<int> > cost;     vector<int> T, X;     vector<int> depth;     vector<bool> vis;     int n;     int root;     Tree(int N = 1e5, int r = 1) {       n = N + 5;       root = r;       anc = vector<vector<int> >(18, vector<int>(n, 0));       depth = vector<int>(n, 0);       vis = vector<bool>(n, false);       X = T = vector<int>(n, 0);       init(root, -1);       for (int d = 1; d < 18; d++) {         for (int x = 0; x < n; x++) {           anc[d][x] = anc[d - 1][anc[d - 1][x]];         }       }     }     void init(int x, int pre) {       static int t = 0;       T[x] = t++;       for (int i = 0; i < adj[x].size(); i++) {         int y = adj[x][i];         if (y == pre) continue;         anc[0][y] = x;         depth[y] = depth[x] + 1;         init(y, x);       }       X[x] = t++;     }     int LCA(int x, int y) {       if (depth[x] < depth[y]) swap(x, y);       for (int w = (1 << 17), d = 17; d >= 0; w /= 2, d--) {         if (depth[x] - depth[y] >= w) {           x = anc[d][x];         }       }       if (x == y) return x;       for (int i = 17; i >= 0; i--) {         if (anc[i][x] != anc[i][y]) {           x = anc[i][x];           y = anc[i][y];         }       }       return anc[0][x];     }     int up(int x, int k) {       for (int w = (1 << 17), d = 17; d >= 0; w /= 2, d--) {         if (k >= w) {           x = anc[d][x];           k -= w;         }       }       return x;     }     int dist(int x, int y) {       int l = LCA(x, y);       return depth[x] + depth[y] - 2 * depth[l];     }     bool isparent(int x, int y) { return LCA(x, y) == x; }   } A;   vector<int> aux[100005];   vector<int> event(100005);   vector<int> val(100005), resv;   vector<bool> out(100005, false), tmp(100005, false);   int n, m, sq, s;   int ans = 0, lans = 0;   vector<int> temp;   vector<int> anc(100005, 0);   int root = 1;   vector<pair<int, int> > edge[100005];   vector<int> lazy(100005, 0);   vector<pair<int, int> > ptr(100005, {0, 0});   void compress(int b) {     for (auto x : temp) {       aux[x].clear();       lazy[x] = 0;       ptr[x] = {0, 0};       edge[x].clear();       anc[x] = 0;       tmp[x] = false;     }     temp.clear();     temp.push_back(1);     for (int i = b * sq; i < (b + 1) * sq && i < m; i++) {       temp.push_back(abs(event[i]));     }     sort((temp).begin(), (temp).end(),          [&](int x, int y) { return A.T[x] < A.T[y]; });     int ss = ((int)(temp).size());     for (int i = 1; i < ss; i++) {       temp.push_back(A.LCA(temp[i - 1], temp[i]));     }     sort((temp).begin(), (temp).end(),          [&](int x, int y) { return A.T[x] < A.T[y]; });     for (auto x : temp) tmp[x] = true;     stack<int> st;     root = 1;     for (auto x : temp) {       while (!st.empty() && A.X[st.top()] < A.T[x]) st.pop();       if (!st.empty() && st.top() != x) {         aux[x].push_back(st.top());         aux[st.top()].push_back(x);         anc[x] = st.top();         int l = A.anc[0][x];         map<int, int> cnt;         while (l != st.top()) {           if (!out[l]) cnt[val[l]]++;           l = A.anc[0][l];         }         for (auto itr : cnt) edge[x].push_back({itr.first, itr.second});         for (int i = 0; i < ((int)(edge[x]).size()); i++) {           if (edge[x][i].first < 0)             ptr[x] = {ptr[x].first + 1, ptr[x].second + edge[x][i].second};           else             break;         }       }       st.push(x);     }   }   int currTree(int x, int pre) {     int v = 0;     if (out[x]) v--;     for (auto y : adj[x]) {       if (y == pre) continue;       v += currTree(y, x);     }     val[x] += v;     return v;   }   bool stat(int x, int pre) {     bool down = false;     if (tmp[x]) down = true;     for (auto y : adj[x]) {       if (y == pre) continue;       down |= stat(y, x);     }     if (!down) {       if (!out[x] && val[x] < 0) lans++;     }     return down;   }   void update(int x, int v) {}   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     cin >> n >> m;     for (int i = 2; i <= n; i++) {       int p;       cin >> p;       adj[p].push_back(i);       adj[i].push_back(p);     }     A = Tree();     for (int i = 1; i <= n; i++) cin >> val[i];     resv = val;     for (int i = 0; i < m; i++) cin >> event[i];     sq = 460;     s = (m - 1) / sq + 1;     for (int b = 0; b < s; b++) {       compress(b);       lans = 0;       stat(1, 0);       for (int i = b * sq; i < (b + 1) * sq && i < m; i++) {         if (event[i] < 0)           out[-event[i]] = false;         else           out[event[i]] = true;         int p = abs(event[i]);         int v = abs(event[i]) / event[i];         while (p != 0) {           lazy[p] += v;           val[p] -= v;           while (ptr[p].first > 0 && edge[p][ptr[p].first - 1].first >= lazy[p])             ptr[p] = {ptr[p].first - 1,                       ptr[p].second - edge[p][ptr[p].first - 1].second};           while (ptr[p].first < ((int)(edge[p]).size()) &&                  edge[p][ptr[p].first].first < lazy[p])             ptr[p] = {ptr[p].first + 1,                       ptr[p].second + edge[p][ptr[p].first].second};           p = anc[p];         }         ans = 0;         int l = -1;         for (auto x : temp) {           if (x == l) continue;           ans += ptr[x].second;           if (!out[x] && val[x] < 0) ans++;           l = x;         }         cout << lans + ans <<    ;       }       val = resv;       currTree(1, 0);     }     cerr << 1.0 * clock() / CLOCKS_PER_SEC << endl;   }   