oj.uz

Submission #776327

# Submission time Handle Problem Language Result Execution time Memory
776327 2023-07-07T16:48:37 Z I_Love_EliskaM_ Highway Tolls (IOI18_highway) C++14
51 / 100
 135 ms 16908 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 1 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 2 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 2 ms 2656 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 9 ms 3376 KB Output is correct
3 Correct 83 ms 8924 KB Output is correct
4 Correct 89 ms 8952 KB Output is correct
5 Correct 100 ms 8896 KB Output is correct
6 Correct 96 ms 8980 KB Output is correct
7 Correct 95 ms 8980 KB Output is correct
8 Correct 101 ms 8888 KB Output is correct
9 Correct 116 ms 8984 KB Output is correct
10 Correct 115 ms 8976 KB Output is correct
11 Correct 113 ms 10644 KB Output is correct
12 Correct 103 ms 11328 KB Output is correct
13 Correct 93 ms 10904 KB Output is correct
14 Correct 87 ms 10524 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 20 ms 5532 KB Output is correct
3 Correct 22 ms 6916 KB Output is correct
4 Correct 91 ms 15380 KB Output is correct
5 Correct 79 ms 15380 KB Output is correct
6 Correct 65 ms 15440 KB Output is correct
7 Correct 92 ms 15364 KB Output is correct
8 Correct 78 ms 15440 KB Output is correct
9 Correct 86 ms 15380 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2640 KB Output is correct
2 Correct 11 ms 3280 KB Output is correct
3 Correct 73 ms 7552 KB Output is correct
4 Correct 90 ms 8908 KB Output is correct
5 Correct 103 ms 8972 KB Output is correct
6 Correct 97 ms 8980 KB Output is correct
7 Correct 103 ms 8984 KB Output is correct
8 Correct 94 ms 8980 KB Output is correct
9 Correct 121 ms 8984 KB Output is correct
10 Correct 91 ms 8980 KB Output is correct
11 Correct 107 ms 9832 KB Output is correct
12 Correct 121 ms 10976 KB Output is correct
13 Correct 94 ms 10472 KB Output is correct
14 Correct 121 ms 10924 KB Output is correct
15 Correct 132 ms 8968 KB Output is correct
16 Correct 95 ms 8984 KB Output is correct
17 Correct 111 ms 10084 KB Output is correct
18 Correct 104 ms 10576 KB Output is correct
19 Correct 95 ms 8952 KB Output is correct
20 Correct 88 ms 11504 KB Output is correct
21 Correct 77 ms 9164 KB Output is correct
22 Correct 69 ms 9176 KB Output is correct
23 Correct 67 ms 9196 KB Output is correct
24 Correct 91 ms 9740 KB Output is correct
25 Correct 135 ms 14768 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 3792 KB Output is correct
2 Correct 15 ms 3868 KB Output is correct
3 Correct 129 ms 13356 KB Output is correct
4 Runtime error 131 ms 16908 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 9 ms 2872 KB Output is incorrect: answered not exactly once.
2 Halted 0 ms 0 KB -