oj.uz

Submission #879552

# Submission time Handle Problem Language Result Execution time Memory
879552 2023-11-27T16:13:43 Z andrei_boaca Highway Tolls (IOI18_highway) C++17
18 / 100
 764 ms 262144 KB 
#include "highway.h"
#include <bits/stdc++.h>
//#include "grader.cpp"
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
int n,m,niv[100005],par[100005],topar[100005],dp[21][100005],in[100005],out[100005],timp;
ll dist,AA,BB;
vector<pii> muchii[100005];
vector<pii> g;
vector<int> w;
bool isancestor(int a,int b)
{
    return in[a]<=in[b]&&out[a]>=out[b];
}
int LCA(int a,int b)
{
    if(niv[a]>niv[b])
        swap(a,b);
    if(isancestor(a,b))
        return a;
    for(int i=20;i>=0;i--)
        if(dp[i][a]!=-1&&!isancestor(dp[i][a],b))
            a=dp[i][a];
    return par[a];
}
void dfs(int nod)
{
    timp++;
    in[nod]=timp;
    dp[0][nod]=par[nod];
    for(int i=1;i<=20;i++)
    {
        if(dp[i-1][nod]==-1)
        {
            dp[i][nod]=-1;
            continue;
        }
        dp[i][nod]=dp[i-1][dp[i-1][nod]];
    }
    for(auto i:muchii[nod])
        if(i.first!=par[nod])
        {
            par[i.first]=nod;
            niv[i.first]=niv[nod]+1;
            topar[i.first]=i.second;
            dfs(i.first);
        }
    out[nod]=timp;
}
void buildniv(int p)
{
    for(int i=0;i<m;i++)
    {
        w[i]=1;
        if(min(niv[g[i].first],niv[g[i].second])<=p)
            w[i]=0;
    }
}
int getnode(vector<int> cand)
{
    while(true)
    {
        if(cand.size()==1)
            return cand[0];
        vector<int> x,y;
        int lg=cand.size();
        for(int i=0;i<cand.size();i++)
        {
            if(i<lg/2)
                x.push_back(cand[i]);
            else
                y.push_back(cand[i]);
        }
        for(int i=0;i<m;i++)
            w[i]=1;
        for(int i:x)
            w[topar[i]]=0;
        ll val=ask(w);
        if(val<dist*BB)
            cand=x;
        else
            cand=y;
    }
    return -1;
}
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});
    }
    for(int i=0;i<n;i++)
        par[i]=-1;
    niv[0]=1;
    dfs(0);
    int nivmax=0;
    for(int i=0;i<n;i++)
        nivmax=max(nivmax,niv[i]);
    for(int i=0;i<m;i++)
        w.push_back(0);
    dist=ask(w)/A;
    int nivlca=nivmax;
    int st=1;
    int dr=nivmax-1;
    while(st<=dr)
    {
        int mij=(st+dr)/2;
        buildniv(mij);
        ll val=ask(w);
        if(val<dist*B)
        {
            nivlca=mij;
            dr=mij-1;
        }
        else
            st=mij+1;
    }
    int nivS=nivlca;
    int nivT=0;
    st=nivlca;
    dr=nivmax-1;
    while(st<=dr)
    {
        int mij=(st+dr)/2;
        buildniv(mij);
        ll nra=2*(mij-nivlca);
        if(nra<=dist)
        {
            ll val=ask(w);
            buildniv(mij-1);
            ll val2=ask(w);
            if(val2==val+2LL*(B-A))
            {
                nivS=mij+1;
                st=mij+1;
                continue;
            }
        }
        dr=mij-1;
    }
    nivT=nivlca+(dist-(nivS-nivlca));
    assert(nivS<=nivT);
    vector<int> c1,c2;
    if(nivS==nivT)
    {
        vector<int> cand;
        for(int i=0;i<n;i++)
            if(niv[i]==nivS)
                cand.push_back(i);
        while(true)
        {
            if(cand.size()==2)
            {
                c1.push_back(cand[0]);
                c2.push_back(cand[1]);
                break;
            }
            vector<int> x,y;
            int lg=cand.size();
            for(int i=0;i<cand.size();i++)
            {
                if(i<lg/2)
                    x.push_back(cand[i]);
                else
                    y.push_back(cand[i]);
            }
            for(int i=0;i<m;i++)
                w[i]=1;
            for(int i:x)
                w[topar[i]]=0;
            ll val=ask(w);
            if(val==1LL*(dist-2)*B+2LL*A)
            {
                cand=x;
                continue;
            }
            if(val==dist*B)
            {
                cand=y;
                continue;
            }
            c1=x;
            c2=y;
            break;
        }
    }
    else
    {
        for(int i=0;i<n;i++)
        {
            if(niv[i]==nivS)
                c1.push_back(i);
            if(niv[i]==nivT)
                c2.push_back(i);
        }
    }
    int T=getnode(c2);
    if(nivS!=nivT)
    {
        c1.clear();
        for(int i=0;i<n;i++)
            if(niv[i]==nivS&&niv[LCA(i,T)]==nivlca)
                c1.push_back(i);
    }
    int S=getnode(c1);
    assert(S!=-1&&T!=-1);
    answer(S,T);
}

Compilation message

highway.cpp: In function 'int getnode(std::vector<int>)':
highway.cpp:68:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |         for(int i=0;i<cand.size();i++)
      |                     ~^~~~~~~~~~~~
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:168:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  168 |             for(int i=0;i<cand.size();i++)
      |                         ~^~~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 2 ms 12888 KB Output is correct
3 Correct 2 ms 12888 KB Output is correct
4 Correct 2 ms 12680 KB Output is correct
5 Correct 2 ms 12888 KB Output is correct
6 Correct 2 ms 12888 KB Output is correct
7 Correct 3 ms 12892 KB Output is correct
8 Correct 2 ms 12888 KB Output is correct
9 Correct 2 ms 12888 KB Output is correct
10 Correct 2 ms 12888 KB Output is correct
11 Correct 2 ms 12888 KB Output is correct
12 Correct 2 ms 12888 KB Output is correct

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 10 ms 13824 KB Output is correct
3 Correct 117 ms 19512 KB Output is correct
4 Correct 125 ms 19272 KB Output is correct
5 Correct 82 ms 19500 KB Output is correct
6 Correct 109 ms 19272 KB Output is correct
7 Correct 90 ms 19496 KB Output is correct
8 Correct 84 ms 19508 KB Output is correct
9 Correct 90 ms 19508 KB Output is correct
10 Correct 89 ms 19276 KB Output is correct
11 Correct 132 ms 20540 KB Output is correct
12 Correct 104 ms 20960 KB Output is correct
13 Correct 133 ms 20444 KB Output is correct
14 Correct 92 ms 19652 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 14200 KB Output is correct
2 Correct 31 ms 15572 KB Output is correct
3 Correct 26 ms 16708 KB Output is correct
4 Correct 80 ms 24840 KB Output is correct
5 Correct 80 ms 24364 KB Output is correct
6 Correct 81 ms 24584 KB Output is correct
7 Correct 124 ms 24364 KB Output is correct
8 Correct 81 ms 24356 KB Output is correct
9 Correct 85 ms 24364 KB Output is correct

Subtask #4
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 16 ms 13824 KB Output is correct
3 Correct 71 ms 18220 KB Output is correct
4 Correct 92 ms 19524 KB Output is correct
5 Correct 92 ms 19500 KB Output is correct
6 Correct 103 ms 19740 KB Output is correct
7 Correct 95 ms 19500 KB Output is correct
8 Correct 102 ms 19512 KB Output is correct
9 Correct 100 ms 19516 KB Output is correct
10 Correct 108 ms 19580 KB Output is correct
11 Correct 119 ms 20256 KB Output is correct
12 Correct 123 ms 21228 KB Output is correct
13 Correct 130 ms 20760 KB Output is correct
14 Correct 133 ms 20952 KB Output is correct
15 Correct 93 ms 19500 KB Output is correct
16 Correct 98 ms 19516 KB Output is correct
17 Correct 109 ms 21124 KB Output is correct
18 Correct 111 ms 20760 KB Output is correct
19 Correct 91 ms 19504 KB Output is correct
20 Correct 110 ms 21864 KB Output is correct
21 Correct 72 ms 20684 KB Output is correct
22 Correct 82 ms 20224 KB Output is correct
23 Incorrect 142 ms 20156 KB Output isn't correct
24 Halted 0 ms 0 KB -

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Runtime error 764 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Runtime error 547 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -