Submission #877777

#	Time	Username	Problem	Language	Result	Execution time	Memory
877777		simona1230	Jail (JOI22_jail)	C++17	61 / 100	5037 ms	168872 KiB

jail

#include <bits/stdc++.h>

using namespace std;
const int maxver=1e6;
const int maxn=9*120000;
int q,n,m;
vector<int> f[maxn];
void read()
{
    cin>>n;
    for(int i=1; i<=n; i++)
        f[i].clear();
    for(int i=1; i<n; i++)
    {
        int x,y;
        cin>>x>>y;
        f[x].push_back(y);
        f[y].push_back(x);
    }
    cin>>m;
}

int num;
int ts[maxn];
int te[maxn];
int dw[maxn];
int up[maxn];

vector<int> v[maxver],o[maxver];

void add_edge(int x,int y)
{
    v[x].push_back(y);
    o[y].push_back(x);
}

void make_tree(int i,int l,int r)
{
    if(l==r)
    {
        ts[i]=num++;
        te[i]=num++;
        //cout<<ts[i]<<" "<<te[i]<<" "<<l<<" "<<r<<endl;
        dw[l]=ts[i];
        up[l]=te[i];
        return;
    }

    ts[i]=num++;
    te[i]=num++;
    //cout<<ts[i]<<" "<<te[i]<<" "<<l<<" "<<r<<endl;
    int mid=(l+r)/2;

    make_tree(i*2,l,mid);
    make_tree(i*2+1,mid+1,r);

    add_edge(ts[i],ts[i*2]);
    add_edge(ts[i],ts[i*2+1]);
    add_edge(te[i*2],te[i]);
    add_edge(te[i*2+1],te[i]);
}

int used[maxn];
int sz[maxn];

void size_(int i)
{
    used[i]=1;
    sz[i]=1;
    for(int j=0; j<f[i].size(); j++)
    {
        int nb=f[i][j];
        if(!used[nb])
        {
            size_(nb);
            sz[i]+=sz[nb];
        }
    }
}

int jump[maxn][21];

int pos[maxn];
int chain[maxn];
int lvl[maxn];
int cnt=1;

void hld(int i,int lead,int level,int par)
{
    pos[i]=cnt++;
    chain[i]=lead;
    lvl[i]=level;

    int maxx=0,big=0;
    for(int j=0; j<f[i].size(); j++)
    {
        int nb=f[i][j];
        if(sz[nb]>maxx&&nb!=par)
        {
            maxx=sz[nb];
            big=nb;
        }
    }

    if(big)
    {
        //cout<<"here "<<i<<" "<<lead<<" "<<ver<<endl;
        hld(big,lead,level+1,i);
        jump[big][0]=i;
    }

    for(int j=0; j<f[i].size(); j++)
    {
        int nb=f[i][j];
        if(nb!=big&&nb!=par)
        {
            hld(nb,nb,level+1,i);
            jump[nb][0]=i;
        }
    }
}

void prec()
{
    for(int j=1; j<=20; j++)
        for(int i=1; i<=n; i++)
            jump[i][j]=jump[jump[i][j-1]][j-1];
}

int make_jump(int x,int k)
{
    for(int i=20; i>=0; i--)
        if(k&(1<<i))x=jump[x][i];
    return x;
}

int lca(int x,int y)
{
    if(lvl[x]<lvl[y])swap(x,y);
    x=make_jump(x,abs(lvl[x]-lvl[y]));
    if(x==y)return x;

    for(int i=20; i>=0; i--)
    {
        if(jump[x][i]!=jump[y][i])
        {
            x=jump[x][i];
            y=jump[y][i];
        }
    }

    return jump[x][0];
}

void update(int i,int l,int r,int ql,int qr,int pr)
{
    if(ql>qr||r<ql||l>qr)return;

    if(ql<=l&&r<=qr)
    {
        add_edge(pr,ts[i]);
        add_edge(te[i],pr);
        return;
    }

    int mid=(l+r)/2;
    update(i*2,l,mid,ql,qr,pr);
    update(i*2+1,mid+1,r,ql,qr,pr);
}
void make_graph()
{
    for(int i=1; i<=m; i++)
    {
        int x,y;
        cin>>x>>y;
        add_edge(dw[pos[x]],i);
        add_edge(i,up[pos[y]]);

        int st,lca_=lca(x,y);
        //cout<<lca_<<endl;

        st=x;
        while(true)
        {
            int ed=chain[st];
            if(lvl[ed]<lvl[lca_])ed=lca_;
            update(1,1,n,pos[ed],pos[st],i);
            //cout<<pos[ed]<<" "<<pos[st]<<endl;
            if(ed==lca_)break;
            st=jump[ed][0];
        }

        st=y;
        while(true)
        {
            int ed=chain[st];
            if(lvl[ed]<lvl[lca_])ed=lca_;
            update(1,1,n,pos[ed],pos[st],i);
            //cout<<pos[ed]<<" "<<pos[st]<<endl;
            if(ed==lca_)break;
            st=jump[ed][0];
        }
    }
}

int comp;
stack<int> topo;
int used1[maxn];
int used2[maxn];

void dfs1(int i)
{
    used1[i]=1;
    for(int j=0; j<v[i].size(); j++)
    {
        int nb=v[i][j];
        if(!used1[nb])
            dfs1(nb);
    }
    topo.push(i);
}

void dfs2(int i)
{
    used2[i]=comp;
    for(int j=0; j<o[i].size(); j++)
    {
        int nb=o[i][j];
        if(!used2[nb])
            dfs2(nb);
    }
}
map<int,int> mp;
void check()
{
    mp.clear();
    for(int i=1; i<=m; i++)
        if(!used1[i])dfs1(i);

    comp=0;
    while(topo.size())
    {
        int ver=topo.top();
        topo.pop();
        if(!used2[ver])
        {
            comp++;
            dfs2(ver);
        }
    }
    //cout<<comp<<" "<<num<<endl;
    bool ans=1;
    for(int i=1;i<=m;i++)
    {
        mp[used2[i]]++;
        if(mp[used2[i]]>1)ans=0;
    }
    if(ans)cout<<"Yes"<<endl;
    else cout<<"No"<<endl;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    cin>>q;
    while(q--)
    {
        read();

        for(int i=1; i<maxver; i++)
        {
            v[i].clear();
            o[i].clear();
        }
        for(int i=1;i<maxn;i++)
        {
            used[i]=pos[i]=used1[i]=0;
            used2[i]=chain[i]=ts[i]=0;
            te[i]=sz[i]=dw[i]=up[i]=lvl[i]=0;
        }
        /*memset(used,0,sizeof(used));
        memset(pos,0,sizeof(pos));
        memset(used1,0,sizeof(used1));
        memset(used2,0,sizeof(used2));
        memset(chain,0,sizeof(chain));
        memset(ts,0,sizeof(ts));
        memset(te,0,sizeof(te));
        memset(sz,0,sizeof(sz));
        memset(dw,0,sizeof(dw));
        memset(up,0,sizeof(up));
        memset(lvl,0,sizeof(lvl));*/
        for(int i=1; i<=n; i++)
            for(int j=0; j<=20; j++)
                jump[i][j]=0;

        size_(1);
        cnt=1;
        hld(1,1,1,-1);
        prec();
        num=m+1;
        make_tree(1,1,n);
        make_graph();
        /*for(int i=1;i<num;i++)
        {
            cout<<i<<": ";
            for(int j=0;j<v[i].size();j++)
            {
                cout<<v[i][j]<<" ";
            }
            cout<<endl;
        }*/
        check();
    }
    return 0;
}
/*
1
6
2 4
4 1
1 5
5 3
3 6
2
2 3
6 1
*/

Compilation message (stderr)

jail.cpp: In function 'void size_(int)':
jail.cpp:70:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |     for(int j=0; j<f[i].size(); j++)
      |                  ~^~~~~~~~~~~~
jail.cpp: In function 'void hld(int, int, int, int)':
jail.cpp:95:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   95 |     for(int j=0; j<f[i].size(); j++)
      |                  ~^~~~~~~~~~~~
jail.cpp:112:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  112 |     for(int j=0; j<f[i].size(); j++)
      |                  ~^~~~~~~~~~~~
jail.cpp: In function 'void dfs1(int)':
jail.cpp:214:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  214 |     for(int j=0; j<v[i].size(); j++)
      |                  ~^~~~~~~~~~~~
jail.cpp: In function 'void dfs2(int)':
jail.cpp:226:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  226 |     for(int j=0; j<o[i].size(); j++)
      |                  ~^~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 28 / 28
• Subtask 5: 12 / 12
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23