oj.uz

Submission #107408

# Submission time Handle Problem Language Result Execution time Memory
107408 2019-04-24T06:22:35 Z shoemakerjo Designated Cities (JOI19_designated_cities) C++14
33 / 100
 969 ms 59240 KB 
#include <bits/stdc++.h>

using namespace std;

using ll = long long;
const int maxn = 200010;
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pil pair<int, pll>
#define pli pair<ll, int>
#define mp make_pair

int n, q;

//we want the seg-tree to go in euler tour order
int qus[maxn];
vector<pil> adj[maxn];

ll ans[maxn]; //store ans for each value
ll dep[maxn]; //distance from root to me
int par[maxn];
ll plink[maxn];
ll pplink[maxn];

int rt; //some global root variable
ll esum = 0LL; //total edge sum
//barebones dfs
void dfs(int u, int p = -1) {
  if (p == -1) {
    dep[u] = 0LL;
    par[u] = -1;
    plink[u] = 0LL;
  }
  for (pil vp : adj[u]) {
    if (vp.first == p) continue;
    dep[vp.first] = dep[u] + vp.second.first; //dep is length to bot
    par[vp.first] = u;
    plink[vp.first] = vp.second.second;
    pplink[vp.first] = vp.second.first;
    dfs(vp.first, u);
  }
}

void dfs1(int u, ll msum = 0LL) {
  ans[1] = min(ans[1], esum - msum);
  for (pil vp : adj[u]) {
    if (vp.first != par[u]) {
      dfs1(vp.first, msum - vp.second.second +
        vp.second.first);
    }
  }
}

void go1() {
  //finds the answer for 1 by itself
  //when I go to a child, I reverse that edge
  //start with all going down
  ans[1] = esum;
  ll csum = 0LL;
  for (int i = 1; i <= n; i++) {
    if (i != rt) csum += plink[i];
  }
  dfs1(rt, csum);
}

pli mdepth[maxn]; //want maxdepth

pii cg;

void dfs2(int u, ll msum) {
  //msum is the sum of everything in
  //consider me to be an lca
  mdepth[u] = {dep[u], u};
  vector<pli> ops;

  for (pil vp : adj[u]) {
    if (vp.first == par[u]) continue;
    dfs2(vp.first, msum - vp.second.second);
    ops.push_back(mdepth[vp.first]);
  }

  sort(ops.begin(), ops.end());
  reverse(ops.begin(), ops.end());
  if (ops.size()) mdepth[u] = ops[0];
  if (ops.size() < 2) return;
  msum += ops[0].first + ops[1].first - dep[u];
  if (esum - msum < ans[2]) {
    ans[2] = esum - msum;
    cg = mp(ops[0].second, ops[1].second);
  }
}

pii go2() {
  //we  consider everything as the lca
  //then we sacrifice a certain amount that "goes down"
  //start with all of the par-links in (par points up)
  ans[2] = esum;
  //   we lose some of the par-links
  ll csum = 0LL;
  for (int i = 1; i <= n; i++) {
    if (i != rt) csum += plink[i];
  }
  dfs2(rt, csum);
  return cg;
}

int st[maxn];
int en[maxn];
vector<int> stuff;

void etour(int u) {
  st[u] = stuff.size();
  stuff.push_back(u);
  for (pil vp : adj[u]) {
    if (vp.first != par[u]) {
      etour(vp.first);
    }
  }
  en[u] = stuff.size()-1;
}

pli seg[maxn*4]; //a max seg tree
ll lazy[maxn*4];

void delaze(int ss, int se, int si) {
  seg[si] = mp(seg[si].first + lazy[si], seg[si].second);
  if (lazy[si] && ss != se) {
    lazy[si*2+1] += lazy[si];
    lazy[si*2+2] += lazy[si];
  }
  lazy[si] = 0;
}

pli query() {
  //get the maximum
  delaze(0, n-1, 0);
  return seg[0];
}

void upd(int us, int ue, ll diff, int ss = 0, int se = n-1,
    int si = 0) {
  delaze(ss, se, si);
  if (us > ue || ss > se || us > se || ue < ss) return;
  if (us <= ss && se <= ue) {
    lazy[si] += diff;
    delaze(ss, se, si);
    return;
  }
  int mid = (ss+se)/2;
  upd(us, ue, diff, ss, mid, si*2+1);
  upd(us, ue, diff, mid+1, se, si*2+2);
  seg[si] = max(seg[si*2+1], seg[si*2+2]);
}

bool isrem[maxn];

void buildtree(int ss = 0, int se  = n-1, int si = 0) {
  if (ss == se) {
    seg[si] = {dep[stuff[ss]], stuff[ss]};
    return;
  }
  int mid = (ss+se)/2;
  buildtree(ss, mid, si*2+1);
  buildtree(mid+1, se, si*2+2);
  seg[si] = max(seg[si*2+1], seg[si*2+2]);
}

void proc(int u) {
  //remove this node
  //go up the parents list
  //all children of me lose going up (keep doing this)
  while (!isrem[u]) {
    // cout << " ----- " << u << endl;
    isrem[u] = true;
    upd(st[u], en[u], 0-pplink[u]);
    u = par[u];
  }
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n;
  int a, b;
  ll c, d;
  for (int i = 0; i < n-1; i++) {
    cin >> a >> b >> c >> d;
    adj[a].emplace_back(b, mp(c, d));
    adj[b].emplace_back(a, mp(d, c));
    esum += c;
    esum += d;
  }
  cin >> q;
  for (int i = 1; i <= q; i++) {
    cin >> qus[i];
  }
  if (n == 2) {
    //just bash
    for (int i = 1; i <= q; i++) {
      if (qus[i] == 2) {
        cout << 0 << endl;
      }
      else {
        cout << min(adj[1][0].second.first,
          adj[1][0].second.second);
      }
    }
    return 0;
  }
  //now we want to root at a non-leaf
  rt = 1;
  for (int i = 2; i <= n; i++) {
    if (adj[i].size() != 1) rt = i;
  }
  dfs(rt);

  go1();
  pii vp = go2();

  // cout << "got 2 : " << vp.first << " " << vp.second << endl;
  //we get the two guys
  rt = par[vp.first];
  dfs(rt); //reset everything (yea)
  etour(rt);
  // cout << "done the dfs" << endl;

  ll cans = ans[2]; //starting answer (will increase)
  //now we do the greedy thing
  buildtree(); //just start all as it is

  // cout << "built the tree" << endl;

  isrem[rt] = true; //basically is removed
  proc(vp.first);
  proc(vp.second);

  for (int i = 3; i <= n; i++) {
    pli tmp = query();
    if (tmp.first != 0) {
      cans -= tmp.first;
      proc(tmp.second);
      // cout << "removing " << tmp.second << " "
      //   << tmp.first << endl;
    }
    ans[i] = cans;
  }

  //now we are just printing out answer (for now - 1/2)
  for (int i = 1; i <= q; i++) {
    cout << ans[qus[i]] << '\n';
  }
  cout.flush();
}

//calculate the answer for one
//use a dp to calculate the answer for two (root at non-leaf)
//greedily add nodes until we get to each val (if none left - do nothing)

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 5120 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 5120 KB Output is correct
2 Correct 848 ms 43324 KB Output is correct
3 Correct 843 ms 52744 KB Output is correct
4 Correct 689 ms 43500 KB Output is correct
5 Correct 704 ms 44160 KB Output is correct
6 Correct 791 ms 45132 KB Output is correct
7 Correct 693 ms 43388 KB Output is correct
8 Correct 969 ms 53992 KB Output is correct
9 Correct 622 ms 44500 KB Output is correct

Subtask #3
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5120 KB Output is correct
2 Correct 830 ms 43420 KB Output is correct
3 Correct 965 ms 52840 KB Output is correct
4 Correct 725 ms 43504 KB Output is correct
5 Correct 720 ms 44324 KB Output is correct
6 Correct 890 ms 45360 KB Output is correct
7 Correct 603 ms 44672 KB Output is correct
8 Correct 844 ms 52708 KB Output is correct
9 Correct 519 ms 44472 KB Output is correct

Subtask #4
0 / 17.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 5120 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 5120 KB Output is correct
2 Correct 848 ms 43324 KB Output is correct
3 Correct 843 ms 52744 KB Output is correct
4 Correct 689 ms 43500 KB Output is correct
5 Correct 704 ms 44160 KB Output is correct
6 Correct 791 ms 45132 KB Output is correct
7 Correct 693 ms 43388 KB Output is correct
8 Correct 969 ms 53992 KB Output is correct
9 Correct 622 ms 44500 KB Output is correct
10 Correct 6 ms 5120 KB Output is correct
11 Correct 830 ms 43420 KB Output is correct
12 Correct 965 ms 52840 KB Output is correct
13 Correct 725 ms 43504 KB Output is correct
14 Correct 720 ms 44324 KB Output is correct
15 Correct 890 ms 45360 KB Output is correct
16 Correct 603 ms 44672 KB Output is correct
17 Correct 844 ms 52708 KB Output is correct
18 Correct 519 ms 44472 KB Output is correct
19 Correct 5 ms 4992 KB Output is correct
20 Correct 793 ms 43440 KB Output is correct
21 Correct 793 ms 59240 KB Output is correct
22 Correct 779 ms 48524 KB Output is correct
23 Correct 777 ms 50288 KB Output is correct
24 Correct 855 ms 48780 KB Output is correct
25 Correct 715 ms 50076 KB Output is correct
26 Correct 855 ms 48876 KB Output is correct
27 Correct 738 ms 49576 KB Output is correct
28 Correct 795 ms 51604 KB Output is correct
29 Correct 857 ms 50408 KB Output is correct
30 Correct 709 ms 49448 KB Output is correct
31 Correct 653 ms 49564 KB Output is correct
32 Correct 828 ms 58344 KB Output is correct
33 Correct 535 ms 50900 KB Output is correct

Subtask #6
0 / 44.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 5120 KB Output isn't correct
2 Halted 0 ms 0 KB -