Submission #881534

# Submission time Handle Problem Language Result Execution time Memory
881534 2023-12-01T12:08:47 Z andrei_boaca Highway Tolls (IOI18_highway) C++17
7 / 100
213 ms 16220 KB
#include "highway.h"
#include <bits/stdc++.h>
//#include "grader.cpp"
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
mt19937 rng(chrono::steady_clock().now().time_since_epoch().count());
int n,m,niv[100005],roots[5];
ll dist,AA,BB,d[3][100005];
int where[100005];
vector<pii> muchii[100005];
vector<pii> g;
vector<int> w;
ll memo[100005],calls;
bool inarb[300005],inx[300005];
int IND;
void bfs(int ind)
{
    for(int i=0;i<n;i++)
        d[ind][i]=1e9;
    d[ind][roots[ind]]=0;
    queue<int> coada;
    coada.push(roots[ind]);
    while(!coada.empty())
    {
        int nod=coada.front();
        coada.pop();
        for(auto i:muchii[nod])
            if(d[ind][i.first]>d[ind][nod]+1)
            {
                d[ind][i.first]=d[ind][nod]+1;
                coada.push(i.first);
            }
    }
}
ll buildniv(ll nivmax,ll ind)
{
    for(int i=0;i<m;i++)
    {
        if(inarb[i]==0)
        {
            w[i]=1;
            continue;
        }
        int a=g[i].first,b=g[i].second;
        if(max(d[ind][a],d[ind][b])<=nivmax)
            w[i]=0;
        else
            w[i]=1;
    }
    return ask(w);
}
ll buildx(int ind)
{
    for(int i=0;i<m;i++)
    {
        if(inarb[i]==0)
        {
            w[i]=1;
            continue;
        }
        int a=g[i].first,b=g[i].second;
        if(d[ind][a]<d[ind][b])
            swap(a,b);
        if(inx[a])
            w[i]=0;
        else
            w[i]=1;
    }
    return ask(w);
}
bool byniv(int i,int j)
{
    int a=max(d[IND][g[i].first],d[IND][g[i].second]);
    int b=max(d[IND][g[j].first],d[IND][g[j].second]);
    return a<b;
}
int plsfind(int ind)
{
    IND=ind;
    for(int i=0;i<m;i++)
        inarb[i]=0;
    for(int i=0;i<n;i++)
        d[ind][i]=1e9;
    ll nivmax=0;
    d[ind][roots[ind]]=0;
    queue<int> coada;
    coada.push(roots[ind]);
    vector<int> edges;
    while(!coada.empty())
    {
        int nod=coada.front();
        nivmax=max(nivmax,d[ind][nod]);
        coada.pop();
        for(auto i:muchii[nod])
            if(where[i.first]==ind&&d[ind][i.first]>d[ind][nod]+1)
            {
                d[ind][i.first]=d[ind][nod]+1;
                inarb[i.second]=1;
                edges.push_back(i.second);
                coada.push(i.first);
            }
    }
    //sort(edges.begin(),edges.end(),byniv);
    for(int i=0;i<m;i++)
        w[i]=1;
    for(int j:edges)
        w[j]=0;
    /*ll val=ask(w);
    if(val==dist*BB)
        return roots[ind];*/
    ll st=0;
    ll dr=edges.size();
    dr--;
    ll ans=-1;
    int poz=0;
    while(st<=dr)
    {
        ll mij=(st+dr)/2;
        for(int i=0;i<m;i++)
            {
                ll a=g[i].first,b=g[i].second;
                if(a==roots[1]&&b==roots[2])
                {
                    w[i]=0;
                    continue;
                }
                if(a==roots[2]&&b==roots[1])
                {
                    w[i]=0;
                    continue;
                }
                if(where[a]!=where[b])
                {
                    w[i]=1;
                    continue;
                }
                if(where[a]!=ind)
                {
                    w[i]=0;
                    continue;
                }
                if(!inarb[i])
                {
                    w[i]=0;
                    continue;
                }
                w[i]=1;
            }
        for(int j=0;j<=mij;j++)
            w[edges[j]]=0;
        ll x=ask(w);
        int p=edges[mij];
        int a=g[p].first;
        int b=g[p].second;
        if(x!=dist*AA)
            st=mij+1;
        else
        {
            poz=mij;
            if(d[ind][a]<d[ind][b])
                swap(a,b);
            ans=a;
            dr=mij-1;
        }
    }
    if(ans==-1)
        return roots[ind];
    return ans;
}
void find_pair(int N, std::vector<int> U, std::vector<int> V, int A, int B)
{
    AA=A;
    BB=B;
    n=N;
    m=U.size();
    for(int i=0;i<m;i++)
    {
        int a=U[i],b=V[i];
        g.push_back({a,b});
        muchii[a].push_back({b,i});
        muchii[b].push_back({a,i});
    }
    w.resize(m);
    dist=ask(w)/A;
    ll st=0;
    ll dr=m-1;
    while(st<=dr)
    {
        ll mij=(st+dr)/2;
        for(int i=0;i<m;i++)
        {
            if(i<=mij)
                w[i]=1;
            else
                w[i]=0;
        }
        ll val=ask(w);
        if(val>dist*A)
        {
            roots[1]=g[mij].first;
            roots[2]=g[mij].second;
            dr=mij-1;
        }
        else
            st=mij+1;
    }
    bfs(1);
    bfs(2);
    for(int i=0;i<n;i++)
    {
        if(d[1][i]<d[2][i])
            where[i]=1;
        if(d[2][i]<d[1][i])
            where[i]=2;
    }
    int S=plsfind(1);
    int T=plsfind(2);
    answer(S,T);
}

Compilation message

highway.cpp: In function 'int plsfind(int)':
highway.cpp:116:9: warning: variable 'poz' set but not used [-Wunused-but-set-variable]
  116 |     int poz=0;
      |         ^~~
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 6612 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 3 ms 6672 KB Output is correct
2 Correct 13 ms 7388 KB Output is correct
3 Correct 106 ms 13872 KB Output is correct
4 Correct 124 ms 13548 KB Output is correct
5 Correct 96 ms 13928 KB Output is correct
6 Correct 85 ms 13676 KB Output is correct
7 Correct 91 ms 13868 KB Output is correct
8 Correct 93 ms 13612 KB Output is correct
9 Correct 117 ms 13612 KB Output is correct
10 Correct 95 ms 13632 KB Output is correct
11 Correct 148 ms 13112 KB Output is correct
12 Correct 137 ms 13456 KB Output is correct
13 Correct 89 ms 13040 KB Output is correct
14 Correct 80 ms 13032 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 7388 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 6676 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 18 ms 7396 KB Output is correct
2 Correct 19 ms 7460 KB Output is correct
3 Correct 120 ms 14260 KB Output is correct
4 Correct 125 ms 14664 KB Output is correct
5 Correct 213 ms 16112 KB Output is correct
6 Correct 148 ms 15932 KB Output is correct
7 Correct 168 ms 16220 KB Output is correct
8 Incorrect 161 ms 15432 KB Output is incorrect: {s, t} is wrong.
9 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 13 ms 7312 KB Output is correct
2 Correct 13 ms 7476 KB Output is correct
3 Correct 137 ms 13836 KB Output is correct
4 Correct 137 ms 14632 KB Output is correct
5 Correct 122 ms 14664 KB Output is correct
6 Incorrect 152 ms 15692 KB Output is incorrect: {s, t} is wrong.
7 Halted 0 ms 0 KB -