Submission #292387

#	Time	Username	Problem	Language	Result	Execution time	Memory
292387		VROOM_VARUN	Factories (JOI14_factories)	C++14	15 / 100	8084 ms	103248 KiB

factories

/*
ID: varunra2
LANG: C++
TASK: factories
*/

#include <bits/stdc++.h>

#include "factories.h"
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions
#define MAXN (int)5e5 + 5
#define MAXSEG 20
int n;
int par[MAXN];
bool use[MAXN];
int sub[MAXN];
VII adj[MAXN];
int lca[MAXN][MAXSEG];
ll d[MAXN];
int tin[MAXN];
int tout[MAXN];
int timer = 0;

int dfs(int u, int v) {
  sub[u] = 1;
  for (auto& x : adj[u]) {
    if (x.x == v or use[x.x]) continue;
    sub[u] += dfs(x.x, u);
  }
  return sub[u];
}

int getCent(int u, int v, int siz) {
  for (auto& x : adj[u]) {
    if (x.x == v or use[x.x]) continue;
    if (sub[x.x] * 2 > siz) {
      return getCent(x.x, u, siz);
    }
  }
  return u;
}

void decompose(int u, int v, int cnt) {
  int cur = getCent(u, -1, dfs(u, -1));
  use[cur] = true;
  par[cur] = v;

  for (auto& x : adj[cur]) {
    if (use[x.x]) continue;
    decompose(x.x, cur, cnt);
  }
}

// inline void init_siz(int N) {
//   n = N;
//   adj.resize(n);
//   par.resize(n);
//   use.resize(n);
//   sub.resize(n);
//   lca.resize(n);
//   d.resize(n);
//   tin.resize(n);
//   tout.resize(n);
//   for (int i = 0; i < n; i++) {
//     lca[i].resize(20);
//     use[i] = false;
//   }
// }

void getAdj(int a[], int b[], int d[]) {
  debug(n);
  for (int i = 0; i < n - 1; i++) {
    int u, v, w;
    u = a[i];
    v = b[i];
    w = d[i];
    adj[u].PB(MP(v, w));
    adj[v].PB(MP(u, w));
  }
}

void dfsLCA(int u, int v) {
  tin[u] = ++timer;
  lca[u][0] = v;
  for (int i = 1; i < 20; i++) {
    int to = lca[u][i - 1];
    if (to == -1)
      lca[u][i] = -1;
    else
      lca[u][i] = lca[to][i - 1];
  }
  for (auto& x : adj[u]) {
    if (x.x == v) continue;
    d[x.x] = d[u] + x.y;
    dfsLCA(x.x, u);
  }
  tout[u] = ++timer;
}

bool isAnc(int u, int v) {
  if (u == -1) return true;
  if (v == -1) return false;
  return tin[u] <= tin[v] and tout[u] >= tout[v];
}

int getLCA(int u, int v) {
  if (isAnc(u, v)) return u;
  if (isAnc(v, u)) return v;
  for (int i = 19; i >= 0; i--) {
    if (!isAnc(lca[u][i], v)) {
      u = lca[u][i];
    }
  }
  return lca[u][0];
}

inline ll getDist(int u, int v) { return d[u] + d[v] - 2 * d[getLCA(u, v)]; }

void Init(int N, int a[], int b[], int d[]) {
  // init_siz(N);
  n = N;
  getAdj(a, b, d);
  decompose(0, -1, 0);
  dfsLCA(0, -1);
}

// MPII mindist;

ll Query(int s, int x[], int t, int y[]) {
  map<int, pair<ll, bool>> mindist;
  for (int i = 0; i < s; i++) {
    // okay so we need to traverse up from x[i];
    int u = x[i];
    while (u != -1) {
      if (mindist[u].y) {
        mindist[u].x = min(mindist[u].x, getDist(u, x[i]));
      } else {
        mindist[u].y = true;
        mindist[u].x = getDist(u, x[i]);
      }
      u = par[u];
    }
  }

  ll ret = (ll)1e17;

  for (int i = 0; i < t; i++) {
    int u = y[i];
    while (u != -1) {
      if (mindist[u].y) {
        ret = min(ret, mindist[u].x + getDist(u, y[i]));
      }
      u = par[u];
    }
  }

  return ret;
}

// int main() {
// #ifndef ONLINE_JUDGE
//   freopen("factories.in", "r", stdin);
//   freopen("factories.out", "w", stdout);
// #endif
//   cin.sync_with_stdio(0);
//   cin.tie(0);

//   int N, q;
//   cin >> N >> q;

//   int a[N - 1];
//   int b[N - 1];
//   int d[N - 1];

//   for (int i = 0; i < N - 1; i++) {
//     cin >> a[i] >> b[i] >> d[i];
//   }

//   Init(N, a, b, d);

//   for (int i = 0; i < q; i++) {
//     int s, t;
//     cin >> s >> t;
//     int x[s];
//     int y[t];
//     for (int j = 0; j < s; j++) {
//       cin >> x[j];
//     }
//     for (int j = 0; j < t; j++) {
//       cin >> y[j];
//     }

//     cout << Query(s, x, t, y) << '\n';
//   }

//   return 0;
// }

Compilation message (stderr)

factories.cpp: In function 'void getAdj(int*, int*, int*)':
factories.cpp:21:20: warning: statement has no effect [-Wunused-value]
   21 | #define debug(...) 42
      |                    ^~
factories.cpp:116:3: note: in expansion of macro 'debug'
  116 |   debug(n);
      |   ^~~~~

• Subtask 1: 15 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67