oj.uz

Submission #879554

# Submission time Handle Problem Language Result Execution time Memory
879554 2023-11-27T16:14:28 Z andrei_boaca Highway Tolls (IOI18_highway) C++17
18 / 100
 742 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!=T);
    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 12888 KB Output is correct
5 Correct 2 ms 12924 KB Output is correct
6 Correct 2 ms 12888 KB Output is correct
7 Correct 2 ms 12888 KB Output is correct
8 Correct 2 ms 12888 KB Output is correct
9 Correct 2 ms 12888 KB Output is correct
10 Correct 3 ms 12888 KB Output is correct
11 Correct 2 ms 12888 KB Output is correct
12 Correct 2 ms 12776 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 16 ms 13656 KB Output is correct
3 Correct 91 ms 19272 KB Output is correct
4 Correct 90 ms 19500 KB Output is correct
5 Correct 96 ms 19496 KB Output is correct
6 Correct 123 ms 19500 KB Output is correct
7 Correct 83 ms 19492 KB Output is correct
8 Correct 104 ms 19492 KB Output is correct
9 Correct 112 ms 19756 KB Output is correct
10 Correct 99 ms 19504 KB Output is correct
11 Correct 100 ms 20312 KB Output is correct
12 Correct 125 ms 20672 KB Output is correct
13 Correct 114 ms 20444 KB Output is correct
14 Correct 99 ms 19892 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14220 KB Output is correct
2 Correct 29 ms 15488 KB Output is correct
3 Correct 25 ms 16708 KB Output is correct
4 Correct 80 ms 24608 KB Output is correct
5 Correct 98 ms 24348 KB Output is correct
6 Correct 96 ms 24376 KB Output is correct
7 Correct 85 ms 24464 KB Output is correct
8 Correct 75 ms 24356 KB Output is correct
9 Correct 107 ms 24348 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 14 ms 13644 KB Output is correct
3 Correct 88 ms 17976 KB Output is correct
4 Correct 103 ms 19724 KB Output is correct
5 Correct 92 ms 19752 KB Output is correct
6 Correct 124 ms 19504 KB Output is correct
7 Correct 104 ms 19264 KB Output is correct
8 Correct 138 ms 19724 KB Output is correct
9 Correct 119 ms 19724 KB Output is correct
10 Correct 134 ms 19512 KB Output is correct
11 Correct 115 ms 19988 KB Output is correct
12 Correct 95 ms 20996 KB Output is correct
13 Correct 132 ms 20536 KB Output is correct
14 Correct 110 ms 20960 KB Output is correct
15 Correct 100 ms 19264 KB Output is correct
16 Correct 91 ms 19752 KB Output is correct
17 Correct 116 ms 21288 KB Output is correct
18 Correct 112 ms 20284 KB Output is correct
19 Correct 108 ms 19264 KB Output is correct
20 Correct 121 ms 21424 KB Output is correct
21 Correct 70 ms 20456 KB Output is correct
22 Correct 80 ms 20456 KB Output is correct
23 Incorrect 97 ms 20616 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 742 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 508 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -