oj.uz

Submission #879548

# Submission time Handle Problem Language Result Execution time Memory
879548 2023-11-27T16:10:24 Z andrei_boaca Highway Tolls (IOI18_highway) C++17
18 / 100
 825 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);
    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);
    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 3 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 12888 KB Output is correct
6 Correct 3 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 2 ms 12888 KB Output is correct
11 Correct 2 ms 12888 KB Output is correct
12 Correct 3 ms 12892 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 14 ms 13664 KB Output is correct
3 Correct 80 ms 19272 KB Output is correct
4 Correct 114 ms 19500 KB Output is correct
5 Correct 86 ms 19396 KB Output is correct
6 Correct 106 ms 19496 KB Output is correct
7 Correct 71 ms 19496 KB Output is correct
8 Correct 115 ms 19500 KB Output is correct
9 Correct 92 ms 19500 KB Output is correct
10 Correct 87 ms 19740 KB Output is correct
11 Correct 109 ms 20336 KB Output is correct
12 Correct 113 ms 20916 KB Output is correct
13 Correct 133 ms 20444 KB Output is correct
14 Correct 153 ms 19892 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 14208 KB Output is correct
2 Correct 28 ms 15732 KB Output is correct
3 Correct 31 ms 16680 KB Output is correct
4 Correct 94 ms 24552 KB Output is correct
5 Correct 73 ms 24596 KB Output is correct
6 Correct 79 ms 24352 KB Output is correct
7 Correct 81 ms 24360 KB Output is correct
8 Correct 77 ms 24592 KB Output is correct
9 Correct 108 ms 24352 KB Output is correct

Subtask #4
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 12888 KB Output is correct
2 Correct 12 ms 13828 KB Output is correct
3 Correct 77 ms 18208 KB Output is correct
4 Correct 109 ms 19732 KB Output is correct
5 Correct 87 ms 19500 KB Output is correct
6 Correct 90 ms 19724 KB Output is correct
7 Correct 126 ms 19496 KB Output is correct
8 Correct 103 ms 19700 KB Output is correct
9 Correct 120 ms 19500 KB Output is correct
10 Correct 94 ms 19736 KB Output is correct
11 Correct 105 ms 20228 KB Output is correct
12 Correct 106 ms 21260 KB Output is correct
13 Correct 158 ms 20992 KB Output is correct
14 Correct 140 ms 21412 KB Output is correct
15 Correct 89 ms 19508 KB Output is correct
16 Correct 92 ms 19508 KB Output is correct
17 Correct 142 ms 21128 KB Output is correct
18 Correct 122 ms 20536 KB Output is correct
19 Correct 82 ms 19528 KB Output is correct
20 Correct 108 ms 21656 KB Output is correct
21 Correct 103 ms 20520 KB Output is correct
22 Correct 83 ms 20744 KB Output is correct
23 Incorrect 102 ms 20204 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 825 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 513 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -