oj.uz

Submission #879550

# Submission time Handle Problem Language Result Execution time Memory
879550 2023-11-27T16:11:37 Z andrei_boaca Highway Tolls (IOI18_highway) C++17
18 / 100
 787 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);
    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 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 12896 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 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 14 ms 13660 KB Output is correct
3 Correct 89 ms 19508 KB Output is correct
4 Correct 84 ms 19260 KB Output is correct
5 Correct 74 ms 19260 KB Output is correct
6 Correct 84 ms 19260 KB Output is correct
7 Correct 93 ms 19520 KB Output is correct
8 Correct 117 ms 19268 KB Output is correct
9 Correct 85 ms 19292 KB Output is correct
10 Correct 85 ms 19512 KB Output is correct
11 Correct 100 ms 20336 KB Output is correct
12 Correct 95 ms 20672 KB Output is correct
13 Correct 106 ms 20664 KB Output is correct
14 Correct 106 ms 19892 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 14376 KB Output is correct
2 Correct 19 ms 15488 KB Output is correct
3 Correct 28 ms 16692 KB Output is correct
4 Correct 77 ms 24604 KB Output is correct
5 Correct 90 ms 24588 KB Output is correct
6 Correct 86 ms 24364 KB Output is correct
7 Correct 107 ms 24348 KB Output is correct
8 Correct 82 ms 24352 KB Output is correct
9 Correct 74 ms 24600 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 9 ms 13652 KB Output is correct
3 Correct 107 ms 17992 KB Output is correct
4 Correct 90 ms 19264 KB Output is correct
5 Correct 137 ms 19500 KB Output is correct
6 Correct 133 ms 19532 KB Output is correct
7 Correct 89 ms 19492 KB Output is correct
8 Correct 95 ms 19508 KB Output is correct
9 Correct 93 ms 19492 KB Output is correct
10 Correct 110 ms 19740 KB Output is correct
11 Correct 128 ms 19784 KB Output is correct
12 Correct 134 ms 21228 KB Output is correct
13 Correct 105 ms 21004 KB Output is correct
14 Correct 115 ms 21396 KB Output is correct
15 Correct 77 ms 19496 KB Output is correct
16 Correct 92 ms 19500 KB Output is correct
17 Correct 108 ms 21136 KB Output is correct
18 Correct 108 ms 20760 KB Output is correct
19 Correct 84 ms 19340 KB Output is correct
20 Correct 105 ms 21640 KB Output is correct
21 Correct 112 ms 20728 KB Output is correct
22 Correct 78 ms 20496 KB Output is correct
23 Incorrect 111 ms 20384 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 787 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 597 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -