Submission #93680

#	Time	Username	Problem	Language	Result	Execution time	Memory
93680		antimirage	Highway Tolls (IOI18_highway)	C++14	5 / 100	216 ms	32608 KiB

highway

#include "highway.h"
#include <bits/stdc++.h>

#define fr first
#define sc second
#define mk make_pair
#define pb push_back

using namespace std;

const int QWE = 1e5 + 5;

int n, len, m, a, b, h[QWE];
vector < vector <pair <int, int> > > g;
vector <int> w, u1, u2;

vector <int> vec[QWE];

void dfs (int v, int level = 0, int p = -1)
{
    h[v] = level;
    for (auto to : g[v])
    {
      if (to.fr == p) continue;
      vec[level + 1].pb(to.sc);
      dfs(to.fr, level + 1, v);
    }
}

int Find(int root)
{
  dfs(root);
  int l = -1, r = vec[len / a].size() - 1;

  while (r - l > 1)
  {
    int md = (l + r) >> 1;
    for (int i = 0; i < m; i++)
      w[i] = 0;
    for (int i = 0; i <= md; i++)
      w[ vec[len / a][i] ] = 1;

    if ( ask(w) != len )
      r = md;
    else
      l = md;
  }
  if ( h[ u1[ vec[len / a][r] ] ] > h[ u2[ vec[len / a][r] ] ] )
      return u1[ vec[len / a][r] ];

  return u2[ vec[len / a][r] ];
}

void find_pair(int  N, std::vector<int> U, std::vector<int> V, int A, int B)
{
  u1 = U;
  u2 = V;
  a = A;
  b = B;
  n = N;
  g.resize(n + 1);

  m = U.size();
  for (int j = 0; j < m; ++j)
  {
    w.pb(0);
    g[ U[j] ].pb( mk( V[j], j) );
    g[ V[j] ].pb( mk( U[j], j) );
  }
  len = ask(w);

  answer( 0, Find(0) );
}
/**
4 3 1 3 0 3
0 1
0 2
0 3
**/

• Subtask 1: 5 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 6
• Subtask 4: 0 / 33
• Subtask 5: 0 / 18
• Subtask 6: 0 / 31