Submission #1073927

#	Time	Username	Problem	Language	Result	Execution time	Memory
1073927		Persia	Election Campaign (JOI15_election_campaign)	C++14	0 / 100	1083 ms	26708 KiB

election_campaign

#include <bits/stdc++.h>
#define rep(i, l, r) for(int i = l; i <= r; i++)
#define rep2(i, l, r) for(int i = l; i >= r; i--)
#define fi first
#define se second
#define bit(i, x) (x >> i & 1)

using namespace std;
const int N = 1e5 + 3;
const int mod = 1e9 + 7;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
long long rnd(long long l, long long r) {
  return uniform_int_distribution<long long>(l, r)(rng);
}

int n, m;
vector<int> G[N];
array<int, 3> qq[N];
int in[N], out[N], rn[N], cnt;
int h[2 * N], rmq[2 * N][19], ct;

void predfs(int u, int par) {
  in[u] = ++cnt;
  rn[cnt] = u;
  rmq[++ct][0] = in[u];
  h[in[u]] = ct;
  for(auto v : G[u]) if (v != par) {
    predfs(v, u);
    rmq[++ct][0] = in[u];
  }
  out[u] = cnt;
}
int lca(int x, int y) {
  x = h[in[x]], y = h[in[y]];
  if (x > y) swap(x, y);
  int kk = 31 - __builtin_clz(y - x + 1);
  return rn[min(rmq[x][kk], rmq[y - (1 << kk) + 1][kk])];
}

namespace sub1{
  int a[2][N];
  void update(int u, int v) {
    int p = lca(u, v);
    a[0][u]++;
    a[0][v]++;
    a[0][p] -= 2;
    a[1][p]++;
  }
  void dfs(int u, int par) {
    for(auto v : G[u]) if (v != par) {
      dfs(v, u);
      a[0][u] += a[0][v];
    }
  }
  long long sol() {
    long long res = 0;
    rep(mask, 0, (1 << m) - 1) {
      long long s = 0;
      rep(i, 1, m) if (bit(i - 1, mask)) {
        s += qq[i][2];
        update(qq[i][0], qq[i][1]);
      }
      dfs(1, -1);
      bool flag = 1;
      rep(i, 1, n) if (a[0][i] + a[1][i] > 1) flag = 0;
      if (flag) res = max(res, s);
      rep(i, 1, n) a[0][i] = a[1][i] = 0;
    }
    return res;
  }
}

int main(int argc, char* argv[]) {
   ios_base::sync_with_stdio(0);
   cin.tie(0); cout.tie(0);

  // freopen("testing.txt", "r", stdin);
//  freopen("outputing.txt", "w", stdout);

  cin >> n;
  rep(i, 1, n - 1) {
    int u, v; cin >> u >> v;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  cin >> m;
  rep(i, 1, m) {
    int u, v, c; cin >> u >> v >> c;
    qq[i] = {u, v, c};
  }
  predfs(1, -1);
  rep(j, 1, 18) rep(i, 1, ct - (1 << (j - 1))) rmq[i][j] = min(rmq[i][j - 1], rmq[i + (1 << (j - 1))][j - 1]);
  cout << sub1::sol();
}

Compilation message (stderr)

election_campaign.cpp: In function 'long long int sub1::sol()':
election_campaign.cpp:60:30: warning: suggest parentheses around '-' inside '>>' [-Wparentheses]
   60 |       rep(i, 1, m) if (bit(i - 1, mask)) {
      |                            ~~^~~
election_campaign.cpp:6:25: note: in definition of macro 'bit'
    6 | #define bit(i, x) (x >> i & 1)
      |                         ^

• Subtask 1: 0 / 10
• Subtask 2: 0 / 5
• Subtask 3: 0 / 5
• Subtask 4: 0 / 30
• Subtask 5: 0 / 10
• Subtask 6: 0 / 40