oj.uz

Submission #776325

# Submission time Handle Problem Language Result Execution time Memory
776325 2023-07-07T16:33:25 Z I_Love_EliskaM_ Highway Tolls (IOI18_highway) C++14
51 / 100
 140 ms 15512 KB 
#include "highway.h"
#include <bits/stdc++.h>
using namespace std;
#define forn(i,n) for(int i=0;i<n;++i)
#define ll long long
#define pb push_back
#define all(x) x.begin(), x.end()
const ll inf = 1e18;
#define pi pair<int,int>
#define f first
#define s second

const int maxn=1e5;
vector<pi> adj[maxn];
pi e[maxn];
vector<int> z;
void dfs(int u, int p) {
  for(auto&ed:adj[u]) {
    int v=ed.f, i=ed.s;
    if (v==p) continue;
    e[i]={u,v};
    z.pb(i);
    dfs(v,u);
  }
}

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void find(int n, vector<int>u, vector<int>v, int a, int b) {
  if (a!=1 || b!=2) exit(0);
  int m=u.size();
  vector<int> f,s;
  ll x;
  forn(it,18) {
    f.clear(), s.clear();
    vector<int> ok(n);
    forn(i,n) ok[i]=rng()&1;
    forn(i,n) (ok[i]?f:s).pb(i);
    if (min(f.size(),s.size())==0) {
      --it; continue;
    }
    vector<int> q(m,0);
    forn(i,m) q[i]=ok[u[i]]==ok[v[i]];
    x = ask(q);
    if (x&1) {
      break;
    }
  }
  if (!(x&1)) exit(0);
  if (f.size()>s.size());
  int l=0, r=f.size()-1;
  while (l<r) {
    int mid=(l+r)>>1;
    vector<int> ok(n);
    for(auto&x:s) ok[x]=1;
    forn(i,mid+1) ok[f[i]]=1;
    vector<int> q(m,0);
    forn(i,m) q[i]=ok[u[i]]==ok[v[i]];
    x = ask(q);
    if (x&1) l=mid+1;
    else r=mid;
  }
  int st = f[r];
  vector<vector<pi>> g(n);
  forn(i,m) {
    g[u[i]].pb({v[i],i});
    g[v[i]].pb({u[i],i});
  }
  vector<int> p(n);
  vector<int> vis(n); vis[st]=1;
  queue<int> q; q.push(st);
  while (q.size()) {
    auto u=q.front();q.pop();
    for(auto&ed:g[u]) {
      int v=ed.f, i=ed.s;
      if (vis[v]) continue;
      vis[v]=1;
      p[v]=i;
      e[i]={u,v};
      q.push(v);
      adj[u].pb({v,i});
    }
  }
  z.clear();
  dfs(st,-1);
  l=0, r=n-2;
  ll S=ask(vector<int>(m,1));
  while (l<r) {
    int mid=(l+r)>>1;
    vector<int> q(m);
    forn(i,mid+1) q[z[i]]=1;
    ll x=ask(q);
    if (x==S) r=mid;
    else l=mid+1;
  }
  answer(st,e[z[r]].s);

}

void find_pair(int n, vector<int>u, vector<int>v, int a, int b) {
  int m=u.size();
  if (m!=n-1) {
    find(n,u,v,a,b);
    return;
  }
  forn(i,n-1) adj[u[i]].pb({v[i],i}), adj[v[i]].pb({u[i],i});
  int k=0; forn(i,n) if (adj[i].size()==1) k=i;
  dfs(k,-1);

  ll s = ask(vector<int>(m,1));

  int l=0, r=n-2;
  while (l<r) {
    int m=(l+r)>>1;
    vector<int> q(n-1);
    forn(i,m+1) q[z[i]]=1;
    ll x=ask(q);
    if (x==s) r=m;
    else l=m+1;
  }

  k = e[z[r]].s;
  //k=0;
  z.clear();
  dfs(k,-1);

  l=0, r=n-2;
  while (l<r) {
    int m=(l+r)>>1;
    vector<int> q(n-1);
    forn(i,m+1) q[z[i]]=1;
    ll x=ask(q);
    if (x==s) r=m;
    else l=m+1;
  }
  answer(k,e[z[r]].s);

}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 1 ms 2640 KB Output is correct
3 Correct 2 ms 2640 KB Output is correct
4 Correct 2 ms 2640 KB Output is correct
5 Correct 2 ms 2640 KB Output is correct
6 Correct 2 ms 2640 KB Output is correct
7 Correct 1 ms 2640 KB Output is correct
8 Correct 2 ms 2640 KB Output is correct
9 Correct 1 ms 2596 KB Output is correct
10 Correct 1 ms 2640 KB Output is correct
11 Correct 1 ms 2640 KB Output is correct
12 Correct 1 ms 2640 KB Output is correct

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 12 ms 3384 KB Output is correct
3 Correct 116 ms 8984 KB Output is correct
4 Correct 79 ms 8980 KB Output is correct
5 Correct 110 ms 8976 KB Output is correct
6 Correct 124 ms 8984 KB Output is correct
7 Correct 94 ms 8980 KB Output is correct
8 Correct 114 ms 8968 KB Output is correct
9 Correct 80 ms 8980 KB Output is correct
10 Correct 125 ms 8984 KB Output is correct
11 Correct 109 ms 10644 KB Output is correct
12 Correct 94 ms 11288 KB Output is correct
13 Correct 87 ms 10932 KB Output is correct
14 Correct 113 ms 10512 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 4048 KB Output is correct
2 Correct 18 ms 5552 KB Output is correct
3 Correct 37 ms 6836 KB Output is correct
4 Correct 74 ms 15468 KB Output is correct
5 Correct 62 ms 15372 KB Output is correct
6 Correct 83 ms 15512 KB Output is correct
7 Correct 95 ms 15436 KB Output is correct
8 Correct 83 ms 15440 KB Output is correct
9 Correct 96 ms 15460 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2640 KB Output is correct
2 Correct 8 ms 3280 KB Output is correct
3 Correct 77 ms 7624 KB Output is correct
4 Correct 84 ms 8972 KB Output is correct
5 Correct 110 ms 8988 KB Output is correct
6 Correct 104 ms 8912 KB Output is correct
7 Correct 88 ms 8988 KB Output is correct
8 Correct 80 ms 8988 KB Output is correct
9 Correct 134 ms 8984 KB Output is correct
10 Correct 107 ms 8964 KB Output is correct
11 Correct 128 ms 9840 KB Output is correct
12 Correct 139 ms 11052 KB Output is correct
13 Correct 123 ms 10528 KB Output is correct
14 Correct 83 ms 10896 KB Output is correct
15 Correct 77 ms 8968 KB Output is correct
16 Correct 90 ms 8916 KB Output is correct
17 Correct 116 ms 10132 KB Output is correct
18 Correct 88 ms 10572 KB Output is correct
19 Correct 72 ms 8984 KB Output is correct
20 Correct 94 ms 11456 KB Output is correct
21 Correct 102 ms 9172 KB Output is correct
22 Correct 73 ms 9172 KB Output is correct
23 Correct 87 ms 9100 KB Output is correct
24 Correct 87 ms 9752 KB Output is correct
25 Correct 140 ms 14768 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 4044 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 2896 KB Output is incorrect: answered not exactly once.
2 Halted 0 ms 0 KB -