Submission #646093

#	Time	Username	Problem	Language	Result	Execution time	Memory
646093		victor_gao	Jail (JOI22_jail)	C++17	5 / 100	24 ms	9696 KiB

jail

//#pragma GCC optimize("Ofast,unroll-loops,O3")
//#pragma GCC optimize("avx,avx2,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,fma,tune=native")
#include<bits/stdc++.h>
//#include<bits/extc++.h>
//#pragma pack(1)
#define fast ios::sync_with_stdio(0); cin.tie(0);
#define int long long
#define pii pair<int,int>
#define x first
#define y second
#define N 120015
using namespace std;
//using namespace __gnu_pbds;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//typedef tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update> order_multiset;
//typedef tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> order_set;
int n,m,st[N],ed[N],fa[N],dep[N],dfn[N],dft=0,low[N],nscc=0,lca[N];
int ac[25][N],in[N],out[N],t=0,nxt_start[N],nxt_end[N];
bool ins[N],vis_start[N],vis_end[N];
stack<int>s;
pii pos[N];
vector<int>g[N],ng[N],scc[N];
void dfs(int p,int lp,int last_start,int last_end){
    nxt_start[p]=last_start;
    nxt_end[p]=last_end;
    fa[p]=lp; ac[0][p]=lp;
    dep[p]=dep[lp]+1; in[p]=++t;
    int nxt_st=last_start;
    int nxt_ed=last_end;
    if (st[p]) nxt_st=st[p];
    if (ed[p]) nxt_ed=ed[p];
    for (auto i:g[p]){
        if (i!=lp) dfs(i,p,nxt_st,nxt_ed);
    }
    out[p]=++t;
}
void build(){
    for (int i=1;i<=20;i++){
        for (int j=1;j<=n;j++)
            ac[i][j]=ac[i-1][ac[i-1][j]];
    }
}
bool check(int a,int b){
    return in[a]<=in[b]&&out[a]>=out[b];
}
int LCA(int a,int b){
    if (check(a,b)) return a;
    else if (check(b,a)) return b;
    for (int i=20;i>=0;i--){
        if (!check(ac[i][a],b)) a=ac[i][a];
    }
    return ac[0][a];
}
void tarjan(int p){
    dfn[p]=low[p]=++dft;
    s.push(p); ins[p]=1;
    for (auto i:ng[p]){
        if (!dfn[i]){
            tarjan(i);
            low[p]=min(low[p],low[i]);
        }
        else if (ins[i]&&dfn[i]<dfn[p])
            low[p]=min(low[p],dfn[i]);
    }
    if (low[p]==dfn[p]){
        nscc++;
        for (int x=0;x!=p;s.pop()){
            x=s.top(); ins[x]=0;
            scc[nscc].push_back(x);
        }
    }
}
void find_start(int dx,int di){
    vector<pii>vt;
    vt.push_back({dx,di});
    while (!vt.empty()){
        int np=vt.back().x;
        if (!nxt_start[np]) break;
        else {
            int ni=nxt_start[np];
            int nx=pos[ni].x;
            while (!vt.empty()){
                auto [x,i]=vt.back();
                if (dep[lca[i]]>dep[nx]){
                    vis_start[i]=1;
                    vt.pop_back();
                    if (!vt.empty()){
               //         cout<<"add1 : "<<i<<" to "<<vt.back().y<<'\n';
                        ng[i].push_back(vt.back().y);
                    } 
                }
                else break;
            }
            vt.push_back({nx,ni});
            if (vis_start[ni]) break;
        }
    }
    while (!vt.empty()){
        auto [x,i]=vt.back();
        vis_start[i]=1;
        vt.pop_back(); 
        if (!vt.empty()){
       //     cout<<"add2 : "<<i<<" to "<<vt.back().y<<'\n';
            ng[i].push_back(vt.back().y);
        } 
    }
}
void find_end(int dx,int di){
    vector<pii>vt;
    vt.push_back({dx,di});
    while (!vt.empty()){
        int np=vt.back().x;
        if (!nxt_end[np]) break;
        else {
            int ni=nxt_end[np];
            int nx=pos[ni].y;
            while (!vt.empty()){
                auto [x,i]=vt.back();
         //       cout<<"Go In "<<lca[i]<<' '<<nx<<" "<<i<<' '<<nx<<'\n';
                if (dep[lca[i]]>dep[nx]){
                    vis_end[i]=1;
                    vt.pop_back();
                    if (!vt.empty()){
         //               cout<<"add1 : "<<vt.back().y<<" to "<<i<<'\n';
                        ng[vt.back().y].push_back(i);
                    } 
                }
                else break;
            }
            vt.push_back({nx,ni});
            if (vis_end[ni]) break;
        }
      //  cout<<di<<" ->\n";
      //  for (auto i:vt)
      //      cout<<i.x<<' '<<i.y<<"\n";
    }
    while (!vt.empty()){
        auto [x,i]=vt.back();
        vis_end[i]=1;
        vt.pop_back();
        if (!vt.empty()){
         //   cout<<"add2 : "<<vt.back().y<<" to "<<i<<'\n';
            ng[vt.back().y].push_back(i);
        } 
    }
}
void reset(){
    while (!s.empty()) s.pop();
    dft=0; nscc=0; t=0;
    for (int i=0;i<=n+5;i++){
        st[i]=0; ed[i]=0; fa[i]=0; dep[i]=0;
        dfn[i]=0; low[i]=0; lca[i]=0; in[i]=0;
        out[i]=0; nxt_start[i]=0; nxt_end[i]=0;
        ins[i]=0; vis_start[i]=0; vis_end[i]=0;
        g[i].clear(); ng[i].clear(); scc[i].clear();
        for (int j=0;j<=23;j++)
            ac[j][i]=0;
    }
}
signed main(){
    fast
    int q; cin>>q;
    while (q--){
        reset();
        cin>>n;
        for (int i=1;i<n;i++){
            int a,b; cin>>a>>b;
            g[a].push_back(b);
            g[b].push_back(a);
        }
        cin>>m;
        for (int i=1;i<=m;i++){
            cin>>pos[i].x>>pos[i].y;
            st[pos[i].x]=i;
            ed[pos[i].y]=i;
        }
        dfs(1,0,0,0);
        build(); in[0]=0; out[0]=1e18;
        for (int i=1;i<=m;i++)
            lca[i]=LCA(pos[i].x,pos[i].y);
        /*
        for (int i=1;i<=n;i++)
            cout<<nxt_start[i]<<" ";
        cout<<'\n';
        for (int i=1;i<=n;i++)
            cout<<nxt_end[i]<<" ";
        cout<<'\n';
        */
        for (int i=1;i<=m;i++){
            find_start(pos[i].x,i);
            find_start(pos[i].y,i);
        //    cout<<i<<" find_start : OK\n";
            find_end(pos[i].y,i);
            find_end(pos[i].x,i);
       //     cout<<i<<" find_end : OK\n";
        }
        for (int i=1;i<=n;i++){
            if (st[i]&&ed[i]){
                ng[st[i]].push_back(ed[i]);
            }
        }
        /*
        for (int i=1;i<=m;i++){
            cout<<i<<" -> ";
            for (auto j:ng[i])
                cout<<j<<" ";
            cout<<'\n';
        }
        */
        for (int i=1;i<=m;i++){
            if (!dfn[i]) tarjan(i);
        }
        if (nscc==m) cout<<"Yes\n";
        else cout<<"No\n";
    }
}

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