Submission #719220

#	Time	Username	Problem	Language	Result	Execution time	Memory
719220		bin9638	Simurgh (IOI17_simurgh)	C++17	51 / 100	1302 ms	3276 KiB

simurgh

#include <bits/stdc++.h>

#ifndef SKY
#include "simurgh.h"
#endif // SKY

using namespace std;

#define N  510
#define ll long long
#define fs first
#define sc second
#define ii pair<int,int>
#define pb push_back

int tmp[N],n,m,times,ktr[N*N],par_id[N];
ii cnt[N],canh[N*N];
vector<ii>g[N];
vector<int>lis;

struct DSU
{
    int lab[N];

    void init()
    {
        memset(lab,-1,sizeof(lab));
    }

    int root(int u)
    {
        if(lab[u]<0)
            return u;
        return(lab[u]=root(lab[u]));
    }

    bool update(int u,int v)
    {
        if((u=root(u))==(v=root(v)))
            return 0;
        if(lab[u]>lab[v])
            swap(u,v);
        lab[u]+=lab[v];
        lab[v]=u;
        return 1;
    }
}T;

#ifdef SKY
int chon[N*N];
int count_common_roads(vector<int>r)
{
    int res=0;
    for(auto i:r)
        res+=chon[i];
    return res;
}
#endif // SKY

int query=0;

int my_ask(vector<int>r)
{
    assert(r.size()==n-1);
    query++;
   // assert(query<=8000);
    return count_common_roads(r);
}

void DFS(int u,int p)
{
    cnt[u].fs=++times;
    for(auto v:g[u])
        if(v.fs!=p)
        {
            par_id[v.fs]=v.sc;
            DFS(v.fs,u);
        }
    cnt[u].sc=times;
}

bool tren(int u,int v)
{
    return (cnt[u].fs<=cnt[v].fs&&cnt[u].sc>=cnt[v].sc);
}

ii get_cnt(int u,int v)
{
    ii res={0,0};
    for(int i=0;i<n;i++)
        if(tren(i,u)+tren(i,v)==1)
        {
            if(ktr[par_id[i]]==-1)
                res.fs++;
                    else res.sc++;
        }
    return res;
}

bool solve(vector<int>s)
{
    if(s.empty())
        return 0;
    vector<int>hoi;
    T.init();
    for(auto u:s)
        T.update(canh[u].fs,canh[u].sc),hoi.pb(u);
    int val=0;
    for(auto i:lis)
        if(T.update(canh[i].fs,canh[i].sc))
            val+=ktr[i],hoi.pb(i);
    int my_ans=my_ask(hoi);
    if(val==my_ans)
    {
        for(auto u:s)
            ktr[u]=0;
        return 0;
    }
    if(val+s.size()==my_ans)
    {
        for(auto u:s)
            ktr[u]=1;
        return 1;
    }
    if(s.size()==1)
    {
        ktr[s[0]]=1;
        return 1;
    }
    vector<int>L,R;
    for(int i=0;i<s.size();i++)
        if(i*2<s.size())
            L.pb(s[i]);
                else R.pb(s[i]);
    if(solve(L)==0)
        return 0;
    return solve(R);
}

vector<int> find_roads(int cc, vector<int> canh_fs, vector<int> canh_sc)
{
    n=cc;
    m=canh_fs.size();
    for(int i=0;i<m;i++)
        canh[i]={canh_fs[i],canh_sc[i]};
    memset(ktr,-1,sizeof(ktr));
    T.init();
    for(int i=0;i<m;i++)
        if(T.update(canh[i].fs,canh[i].sc))
        {
            lis.pb(i);
           // cout<<i<<endl;
            g[canh[i].fs].pb({canh[i].sc,i});
            g[canh[i].sc].pb({canh[i].fs,i});
        }
    memset(par_id,-1,sizeof(par_id));
    DFS(0,-1);
    int val=my_ask(lis);
    //cout<<val<<endl;
   for(int i=0;i<m;i++)
   {
       ii cc=get_cnt(canh[i].fs,canh[i].sc);
       if(cc.fs>0&&cc.fs+cc.sc>1)
       {
            int u=canh[i].fs,v=canh[i].sc;
            if(cc.sc==0)
            {
                int kt=0;
                for(int j=0;j<n;j++)
                    if(tren(j,u)+tren(j,v)==1)
                    {
                        vector<int>luu=lis;
                        for(int t=0;t<n-1;t++)
                            if(luu[t]==par_id[j])
                                luu[t]=i;
                        tmp[j]=my_ask(luu);
                        if(tmp[j]>val)
                            kt=1;
                    }
                for(int j=0;j<n;j++)
                    if(tren(j,u)+tren(j,v)==1)
                    {
                       if(kt==0)
                       {
                           ktr[par_id[j]]=(tmp[j]<val);
                       }else
                       {
                            ktr[par_id[j]]=(tmp[j]==val);
                       }
                    }
            }else
            {
                int kt=0;
                for(int j=0;j<n;j++)
                    if(tren(j,u)+tren(j,v)==1&&ktr[par_id[j]]!=-1)
                    {
                        vector<int>luu=lis;
                        for(int t=0;t<n-1;t++)
                            if(luu[t]==par_id[j])
                                luu[t]=i;
                        if(ktr[par_id[j]]==0)
                        {
                            kt=(my_ask(luu)>val);
                        }else
                        {
                            kt=(my_ask(luu)==val);
                        }
                        break;
                    }
                 for(int j=0;j<n;j++)
                    if(tren(j,u)+tren(j,v)==1&&ktr[par_id[j]]==-1)
                    {
                        vector<int>luu=lis;
                        for(int t=0;t<n-1;t++)
                            if(luu[t]==par_id[j])
                                luu[t]=i;
                        tmp[j]=my_ask(luu);
                       if(kt==0)
                       {
                           ktr[par_id[j]]=(tmp[j]<val);
                       }else
                       {
                            ktr[par_id[j]]=(tmp[j]==val);
                       }
                    }
            }
       }
   }
    for(auto i:lis)
        if(ktr[i]==-1)
            ktr[i]=1;
    while(1)
    {
        int kt=0,sl=0;
        for(int i=0;i<m;i++)
            if(ktr[i]==-1)
                kt=1;
        if(kt==0)
            break;
        for(int i=0;i<m;i++)
            if(ktr[i]==1)
                sl++;
        if(sl==n-1)
            break;
        T.init();
        vector<int>s;
        for(int i=0;i<m;i++)
            if(ktr[i]==-1&&T.update(canh[i].fs,canh[i].sc))
                s.pb(i);
        solve(s);
    }
    vector<int>kq;
    for(int i=0;i<m;i++)
        if(ktr[i]==1)
            kq.pb(i);
    return kq;
}

#ifdef SKY
int main()
{
    freopen("A.inp","r",stdin);
    freopen("A.out","w",stdout);
    ios::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    int n,m;
    cin>>n>>m;
    vector<int>u,v;
    for(int i=1;i<=m;i++)
    {
        int x,y;
        cin>>x>>y;
        u.pb(x);
        v.pb(y);
    }
    for(int i=1;i<n;i++)
    {
        int u;
        cin>>u;
      //  cout<<u<<endl;
        chon[u]=1;
    }
    vector<int>kq=find_roads(n,u,v);
    cout<<"ASK "<<query<<endl;
    for(int i=0;i<n-1;i++)cout<<kq[i]<<"\n";
    return 0;
}
#endif

Compilation message (stderr)

In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from simurgh.cpp:1:
simurgh.cpp: In function 'int my_ask(std::vector<int>)':
simurgh.cpp:64:20: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   64 |     assert(r.size()==n-1);
      |            ~~~~~~~~^~~~~
simurgh.cpp: In function 'bool solve(std::vector<int>)':
simurgh.cpp:119:20: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  119 |     if(val+s.size()==my_ans)
      |        ~~~~~~~~~~~~^~~~~~~~
simurgh.cpp:131:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  131 |     for(int i=0;i<s.size();i++)
      |                 ~^~~~~~~~~
simurgh.cpp:132:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  132 |         if(i*2<s.size())
      |            ~~~^~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 17 / 17
• Subtask 3: 21 / 21
• Subtask 4: 0 / 19
• Subtask 5: 0 / 30