Submission #659895

#	Time	Username	Problem	Language	Result	Execution time	Memory
659895		600Mihnea	Magic Tree (CEOI19_magictree)	C++17	100 / 100	688 ms	35604 KiB

magictree

bool home = 0;
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N = (int) 1e5 + 7;
const ll INF = (ll) 1e18 + 7;
int n;
int m;
int k;
int p[N];
int type[N];
int w[N];
int sub[N];
int bg[N];
int low[N];
int high[N];
int ord[N];
int top;
vector<int> g[N];
int Counter = 0;
int last_seen[N];
ll tree[4 * N];
ll lazy_a[4 * N];
ll lazy_b[4 * N];
ll lazy_max[4 * N];

void push(int v, int tl, int tr) {
  if (lazy_a[v] != 1 || lazy_b[v] != 0) {
    tree[v] = tree[v] * lazy_a[v] + lazy_b[v];
    if (tl < tr) {
      for (int v2 = 2 * v; v2 <= 2 * v + 1; v2++) {
        lazy_a[v2] *= lazy_a[v];
        lazy_b[v2] *= lazy_a[v];
        lazy_b[v2] += lazy_b[v];
        lazy_max[v2] = lazy_max[v2] * lazy_a[v] + lazy_b[v];
      }
    }
    lazy_a[v] = 1;
    lazy_b[v] = 0;
  }
  if (lazy_max[v]) {
    tree[v] = max(tree[v], lazy_max[v]);
    if (tl < tr) {
      for (int v2 = 2 * v; v2 <= 2 * v + 1; v2++) {
        lazy_max[v2] = max(lazy_max[v2], lazy_max[v]);
      }
    }
    lazy_max[v] = 0;
  }
}

void pushcoef(int v, int tl, int tr, int l, int r, ll a, ll b) {
  push(v, tl, tr);
  if (tr < l || r < tl) {
    return;
  }
  if (l <= tl && tr <= r) {
    lazy_a[v] = a;
    lazy_b[v] = b;
    push(v, tl, tr);
    return;
  }
  int tm = (tl + tr) / 2;
  pushcoef(2 * v, tl, tm, l, r, a, b);
  pushcoef(2 * v + 1, tm + 1, tr, l, r, a, b);
  tree[v] = max(tree[2 * v], tree[2 * v + 1]);
}

void maxup(int v, int tl, int tr, int l, int r, ll x) {
  push(v, tl, tr);
  if (tr < l || r < tl) {
    return;
  }
  if (l <= tl && tr <= r) {
    lazy_max[v] = x;
    push(v, tl, tr);
    return;
  }
  int tm = (tl + tr) / 2;
  maxup(2 * v, tl, tm, l, r, x);
  maxup(2 * v + 1, tm + 1, tr, l, r, x);
  tree[v] = max(tree[2 * v], tree[2 * v + 1]);
}

ll get_max(int v, int tl, int tr, int l, int r) {
  push(v, tl, tr);
  if (tr < l || r < tl) {
    return -INF;
  }
  if (l <= tl && tr <= r) {
    return tree[v];
  }
  int tm = (tl + tr) / 2;
  return max(get_max(2 * v, tl, tm, l, r), get_max(2 * v + 1, tm + 1, tr, l, r));
}

void pushcoef(int l, int r, ll a, ll b) {
  pushcoef(1, 1, k, l, r, a, b);
}

void maxup(int l, int r, ll x) {
  maxup(1, 1, k, l, r, x);
}

ll get_max(int l, int r) {
  if (l > r) {
    return 0;
  }
  if (l == 0) {
    assert(r == 0);
    return 0;
  }
  assert(1 <= l && l <= r && r <= k);
  return get_max(1, 1, k, l, r);
}

void bu(int a) {
  low[a] = ++top;
  ord[top] = a;
  sub[a] = 1;
  for (auto &b : g[a]) {
    bu(b);
    sub[a] += sub[b];
    if (sub[b] > sub[bg[a]]) {
      bg[a] = b;
    }
  }
  high[a] = top;
}


vector<pair<int, ll>> get_and_clr_dp(int v) {
  Counter++;
  vector<pair<int, ll>> sol;
  for (int j = low[v]; j <= high[v]; j++) {
    if (int i = type[ord[j]]) {
      if (last_seen[i] == Counter) {
        continue;
      }
      last_seen[i] = Counter;
      sol.push_back({i, get_max(i, i) - get_max(i - 1, i - 1)});
    }
  }
  pushcoef(1, k, 0, 0);
  return sol;
}

ll dpaux[N];

void solve(int a) {
  if (g[a].empty()) {
    if (type[a]) {
      pushcoef(type[a], k, 1, w[a]);
    }
  } else {
    assert(bg[a] != -1);
    vector<vector<pair<int, ll>>> all;
    for (auto &b : g[a]) {
      if (b != bg[a]) {
        solve(b);
        all.push_back(get_and_clr_dp(b));
        continue;
      }
    }
    {
      int b = bg[a];
      solve(b);
      for (auto &v : all) {
        for (auto &g : v) {
          pushcoef(g.first, k, 1, g.second);
        }
      }
      if (type[a]) {
        pushcoef(type[a], type[a], 1, w[a]);
        maxup(type[a], k, get_max(type[a], type[a]));
      }
    }
  }
}

int main() {

  if (!home) {
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  } else {
    freopen("input.txt", "r", stdin);
  }


  for (int i = 0; i < 4 * N; i++) {
    lazy_a[i] = 1;
    lazy_b[i] = 0;
    lazy_max[i] = 0;
  }

  cin >> n >> m >> k;
  if (0) {
    cout << "  : ";
    for (int i = 1; i <= k; i++) {
      cout << i << " ";
    }
    cout << "\n";
  }
  for (int i = 2; i <= n; i++) {
    cin >> p[i];
    g[p[i]].push_back(i);
  }
  for (int i = 1; i <= m; i++) {
    int v;
    cin >> v;
    cin >> type[v];
    cin >> w[v];
  }
  {
    map<int, int> mp;
    for (int i = 1; i <= n; i++) {
      if (type[i]) {
        mp[type[i]] = 0;
      }
    }
    int cr = 0;
    for (auto &it : mp) {
      it.second = ++cr;
    }
    for (int i = 1; i <= n; i++) {
      if (type[i]) {
        type[i] = mp[type[i]];
      }
    }
    k = min(k, m);
  }
  bu(1);
  solve(1);
  cout << get_max(k, k) << "\n";
  return 0;
}
/**

dp[vertex][last_value] = ?



**/

Compilation message (stderr)

magictree.cpp: In function 'int main()':
magictree.cpp:189:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  189 |     freopen("input.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 3 / 3
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 16 / 16
• Subtask 6: 13 / 13
• Subtask 7: 22 / 22
• Subtask 8: 17 / 17