oj.uz

Submission #776326

# Submission time Handle Problem Language Result Execution time Memory
776326 2023-07-07T16:47:54 Z I_Love_EliskaM_ Highway Tolls (IOI18_highway) C++14
51 / 100
 135 ms 16820 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);
      z.pb(i);
    }
  }
  l=0, r=n-2;
  ll S=ask(vector<int>(m,1));
  while (l<r) {
    int mid=(l+r)>>1;
    vector<int> q(m,1);
    for(int i=mid+1;i<z.size();++i) q[z[i]]=0;
    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);

}

Compilation message

highway.cpp: In function 'void find(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:89:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |     for(int i=mid+1;i<z.size();++i) q[z[i]]=0;
      |                     ~^~~~~~~~~

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 1 ms 2640 KB Output is correct
5 Correct 1 ms 2640 KB Output is correct
6 Correct 1 ms 2640 KB Output is correct
7 Correct 2 ms 2640 KB Output is correct
8 Correct 1 ms 2640 KB Output is correct
9 Correct 1 ms 2640 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 13 ms 3280 KB Output is correct
3 Correct 112 ms 8960 KB Output is correct
4 Correct 111 ms 8868 KB Output is correct
5 Correct 90 ms 8984 KB Output is correct
6 Correct 100 ms 8980 KB Output is correct
7 Correct 84 ms 8900 KB Output is correct
8 Correct 93 ms 8976 KB Output is correct
9 Correct 109 ms 8968 KB Output is correct
10 Correct 102 ms 8916 KB Output is correct
11 Correct 87 ms 10716 KB Output is correct
12 Correct 103 ms 11288 KB Output is correct
13 Correct 119 ms 10896 KB Output is correct
14 Correct 133 ms 10460 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 4048 KB Output is correct
2 Correct 15 ms 5484 KB Output is correct
3 Correct 22 ms 6852 KB Output is correct
4 Correct 63 ms 15440 KB Output is correct
5 Correct 110 ms 15392 KB Output is correct
6 Correct 79 ms 15520 KB Output is correct
7 Correct 92 ms 15388 KB Output is correct
8 Correct 66 ms 15420 KB Output is correct
9 Correct 83 ms 15376 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 12 ms 3372 KB Output is correct
3 Correct 74 ms 7608 KB Output is correct
4 Correct 114 ms 8980 KB Output is correct
5 Correct 89 ms 9008 KB Output is correct
6 Correct 80 ms 8980 KB Output is correct
7 Correct 94 ms 8980 KB Output is correct
8 Correct 102 ms 8960 KB Output is correct
9 Correct 85 ms 8984 KB Output is correct
10 Correct 81 ms 8984 KB Output is correct
11 Correct 97 ms 9840 KB Output is correct
12 Correct 85 ms 10980 KB Output is correct
13 Correct 108 ms 10572 KB Output is correct
14 Correct 121 ms 10896 KB Output is correct
15 Correct 83 ms 8972 KB Output is correct
16 Correct 91 ms 9128 KB Output is correct
17 Correct 89 ms 10192 KB Output is correct
18 Correct 111 ms 10576 KB Output is correct
19 Correct 85 ms 9048 KB Output is correct
20 Correct 132 ms 11472 KB Output is correct
21 Correct 82 ms 9164 KB Output is correct
22 Correct 111 ms 9172 KB Output is correct
23 Correct 68 ms 9100 KB Output is correct
24 Correct 104 ms 9740 KB Output is correct
25 Correct 112 ms 14668 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 3828 KB Output is correct
2 Correct 12 ms 3876 KB Output is correct
3 Correct 113 ms 13368 KB Output is correct
4 Runtime error 135 ms 16820 KB Execution killed with signal 11
5 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Incorrect 8 ms 2896 KB Output is incorrect: answered not exactly once.
2 Halted 0 ms 0 KB -