Submission #1040407

#	Time	Username	Problem	Language	Result	Execution time	Memory
1040407		12345678	Inside information (BOI21_servers)	C++17	100 / 100	2076 ms	71000 KiB

servers

#include <bits/stdc++.h>
 
using namespace std;
 
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

const int nx=250005, kx=18, mod=200;
 
int n, k, a[nx], b[nx], idx[nx], cnt[nx], lvl[nx], pa[nx][kx], up[nx], dn[nx], pw[nx], t, in[nx], out[nx], lst, dp[nx], l[nx], r[nx], pts[nx];
char opr[nx];
vector<pair<int, int>> d[nx];
 
void dfs(int u, int p)
{
    lvl[u]=lvl[p]+1;
    in[u]=++t;
    up[u]=p;
    if (pw[u]<pw[p]) up[u]=up[p];
    dn[u]=p;
    if (pw[u]>pw[p]) dn[u]=dn[p];
    pa[u][0]=p;
    for (int i=1; i<kx; i++) pa[u][i]=pa[pa[u][i-1]][i-1];
    for (auto [v, w]:d[u]) if (v!=p) pw[v]=w, dfs(v, u);
    out[u]=t;
}
 
pair<int, int> query1(int idx)
{
    if (in[a[idx]]<=in[b[idx]]&&in[b[idx]]<=out[a[idx]]) return {a[idx], 0};
    int tmp=a[idx];
    for (int i=kx-1; i>=0; i--) if (!(in[pa[tmp][i]]<=in[b[idx]]&&in[b[idx]]<=out[pa[tmp][i]])) tmp=pa[tmp][i];
    if (lvl[up[a[idx]]]>lvl[pa[tmp][0]]) return {-1, 0};
    return {pa[tmp][0], pw[tmp]};
}
 
int query(int i)
{
    auto [u, lst]=query1(i);
    if (u==-1) return 0;
    else
    {
        if (u==b[i]&&lst<=cnt[i]) return 1;
        else if (u==b[i]&&lst>cnt[i]) return 0;
        else
        {
            int vl=pw[b[i]], tmp=b[i];
            if (lvl[dn[b[i]]]>lvl[u]||pw[b[i]]>cnt[i]) return 0;
            else
            {
                for (int j=kx-1; j>=0; j--) if (lvl[pa[tmp][j]]>lvl[u]) tmp=pa[tmp][j];
                if (lst<pw[tmp]) return 1;
                else return 0;
            }
        }
    }
}
 
void solve()
{
    int vs[n+1][n+1], xx, yy;
    char cc;
    for (int i=1; i<=n; i++) for (int j=1; j<=n; j++) vs[i][j]=0;
    cin>>k;
    for (int i=1; i<=n; i++) vs[i][i]=i;
    for (int i=1; i<n+k; i++)
    {
        cin>>cc;
        if (cc=='S')
        {
            cin>>xx>>yy;
            for (int j=1; j<=n; j++) vs[xx][j]=vs[yy][j]=(vs[xx][j]||vs[yy][j]);
        }
        if (cc=='Q') cin>>xx>>yy, cout<<(vs[xx][yy]?"yes\n":"no\n");
        if (cc=='C')
        {
            cin>>xx;
            int cnt=0;
            for (int j=1; j<=n; j++) if (vs[j][xx]) cnt++;
            cout<<cnt<<'\n';
        }
    }
}

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n;
    if (n<=4000) return solve(), 0;
    cin>>k;
    for (int i=1; i<=n; i++) pts[i]=i, dp[i]=1;
    for (int i=1; i<n+k; i++)
    {
        cin>>opr[i];
        cnt[i]=cnt[i-1];
        if (opr[i]=='S') cin>>a[i]>>b[i], idx[++cnt[i]]=i, d[a[i]].push_back({b[i], cnt[i]}), d[b[i]].push_back({a[i], cnt[i]}), l[cnt[i]+n]=pts[a[i]], r[cnt[i]+n]=pts[b[i]], pts[a[i]]=pts[b[i]]=cnt[i]+n;
        if (opr[i]=='Q') cin>>b[i]>>a[i];
        if (opr[i]=='C') cin>>a[i];
    }
    dfs(1, 1);
    for (int i=1; i<n+k; i++)
    {
        if (opr[i]=='S')
        {
            if ((cnt[i]%mod)==0)
            {
                for (int j=1; j<=n+cnt[j]; j++) dp[j]=1;
                for (int j=n+cnt[i]; j>=n+1; j--) dp[l[j]]+=dp[j], dp[r[j]]+=dp[j];
                lst=cnt[i];
            }
        }
        if (opr[i]=='Q') cout<<(query(i)?"yes\n":"no\n");
        if (opr[i]=='C') 
        {
            int tmp=dp[a[i]];
            for (int j=lst+1; j<=cnt[i]; j++) 
            {
                int f=1;
                b[i]=a[idx[j]];
                if (!query(i)) f=0;
                b[i]=b[idx[j]];
                if (!query(i)) f=0;
                tmp+=f;
            }
            cout<<tmp<<'\n';
        }
    }
}

Compilation message (stderr)

servers.cpp: In function 'int query(int)':
servers.cpp:47:17: warning: unused variable 'vl' [-Wunused-variable]
   47 |             int vl=pw[b[i]], tmp=b[i];
      |                 ^~

• Subtask 1: 2.5 / 2.5
• Subtask 2: 2.5 / 2.5
• Subtask 3: 2.5 / 2.5
• Subtask 4: 2.5 / 2.5
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 12.5 / 12.5
• Subtask 10: 12.5 / 12.5
• Subtask 11: 17.5 / 17.5
• Subtask 12: 17.5 / 17.5