Submission #402715

#	Time	Username	Problem	Language	Result	Execution time	Memory
402715		rrrr10000	Inside information (BOI21_servers)	C++14	100 / 100	696 ms	39652 KiB

servers

#include <bits/stdc++.h>
using namespace std;
#define rep(i, n)  for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define pb emplace_back
#define lb(v,k) (lower_bound(all(v),(k))-v.begin())
#define ub(v,k) (upper_bound(all(v),(k))-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
#define dame(a) {out(a);return 0;}
#define decimal cout<<fixed<<setprecision(15);
#define all(a) a.begin(),a.end()
#define rsort(a) {sort(all(a));reverse(all(a));}
#define dupli(a) {sort(all(a));a.erase(unique(all(a)),a.end());}
typedef long long ll;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef tuple<ll,ll,ll,ll> PPP;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vvvvi=vector<vvvi>;
using vp=vector<P>;
using vvp=vector<vp>;
using vb=vector<bool>;
using vvb=vector<vb>;
const ll inf=1001001001001001001;
const ll INF=1001001001;
const ll mod=1000000007;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outvvp(T v){rep(i,v.size())outvp(v[i]);}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void outset(T s){auto itr=s.begin();while(itr!=s.end()){if(itr!=s.begin())cout<<' ';cout<<*itr;itr++;}cout<<'\n';}
void outs(ll a,ll b){if(a>=inf-100)out(b);else out(a);}
ll gcd(ll a,ll b){if(b==0)return a;return gcd(b,a%b);}
ll modpow(ll a,ll b){ll res=1;a%=mod;while(b){if(b&1)res=res*a%mod;a=a*a%mod;b>>=1;}return res;}
class BIT{
    vi bit;ll N;
public:
    ll sum(ll i){
        chmin(i,N);
        ll res=0;
        for(ll j=i-1;j>=0;j=(j&(j+1))-1)res+=bit[j];
        return res;
    }
    BIT(ll n):N(n){bit.resize(N);}
    void add(ll i,ll x){
        for(int j=i;j<N;j|=j+1)bit[j]+=x;
    }
    ll get(ll a,ll b){
        return sum(b)-sum(a);
    }
};
class UF{
    vi data;stack<P> st;
public:
    UF(ll n){
        data=vi(n,1);
    }
    bool merge(ll x,ll y,bool undo=false){
        x=root(x);y=root(y);
        if(data[x]>data[y])swap(x,y);
        if(undo){st.emplace(y,data[y]);st.emplace(x,data[x]);}
        if(x==y)return false;
        data[y]+=data[x];data[x]=-y;
        return true;
    }
    ll root(ll i){if(data[i]>0)return i;return root(-data[i]);}
    ll getsize(ll i){return data[root(i)];}
    bool same(ll a,ll b){return root(a)==root(b);}
    void undo(){rep(i,2){data[st.top().fi]=st.top().se;st.pop();}}
};
int main(){
    ll n,q;cin>>n>>q;
    vvp g(n);
    ll cur=0,cnt_query=0;
    vi ans(q);
    UF uf(n);
    vvp q1(n),q2(n);
    rep(i,q+n-1){
        char c;cin>>c;
        if(c=='S'){
            ll a,b;cin>>a>>b;a--;b--;
            g[a].pb(cur,b);g[b].pb(cur,a);cur++;
            uf.merge(a,b);
        }
        if(c=='Q'){
            ll a,b;cin>>a>>b;a--;b--;
            if(uf.same(a,b))q1[b].pb(a,cnt_query);
            ans[cnt_query++]=-2;
        }
        if(c=='C'){
            ll a;cin>>a;a--;
            q2[a].pb(cur,cnt_query++);
        }
    }
    rep(i,n)rsort(g[i]);
    vb dead(n,false);vi sub(n);
    function<ll(ll,ll,ll)> find_cen=[&](ll i,ll p,ll s){
        for(auto x:g[i])if(!dead[x.se]&&x.se!=p&&sub[x.se]*2>s)return find_cen(x.se,i,s);
        return i;
    };
    function<ll(ll,ll)> init=[&](ll i,ll p){
        sub[i]=1;
        for(auto x:g[i])if(!dead[x.se]&&x.se!=p)sub[i]+=init(x.se,i);
        return sub[i];
    };
    auto getcen=[&](ll i){
        init(i,-1);
        return find_cen(i,-1,sub[i]);
    };
    BIT bit(n);
    vb ok(n,false);
    function<void(ll)> solve=[&](ll c){
        vi tmp,tmp2;
        c=getcen(c);
        ok[c]=true;tmp2.pb(c);
        rep(idx,g[c].size())if(!dead[g[c][idx].se]){
            queue<PP> que;
            que.emplace(g[c][idx].se,g[c][idx].fi,-1);
            while(!que.empty()){
                ll i,prev,par;tie(i,prev,par)=que.front();que.pop();
                for(auto x:q1[i]){
                    if(ok[x.fi])ans[x.se]=-1;
                }
                for(auto x:q2[i]){
                    if(g[c][idx].fi<x.fi)ans[x.se]+=bit.sum(x.fi)+1;
                }
                for(auto x:g[i])if(x.se!=par&&!dead[x.se]&&x.fi<prev){
                    que.emplace(x.se,x.fi,i);
                }
            }
            que.emplace(g[c][idx].se,g[c][idx].fi,-1);
            while(!que.empty()){
                ll i,prev,par;tie(i,prev,par)=que.front();que.pop();ok[i]=true;tmp2.pb(i);
                bit.add(prev,1);tmp.pb(prev);
                for(auto x:g[i])if(x.se!=par&&!dead[x.se]&&x.fi>prev){
                    que.emplace(x.se,x.fi,i);
                }
            }
        }
        for(auto x:q1[c]){
            if(ok[x.fi])ans[x.se]=-1;
        }
        for(auto x:q2[c]){
            ans[x.se]+=bit.sum(x.fi)+1;
        }
        for(ll x:tmp)bit.add(x,-1);for(ll x:tmp2)ok[x]=false;
        dead[c]=true;
        for(auto x:g[c])if(!dead[x.se])solve(x.se);
    };solve(0);
    for(ll x:ans){
        if(x==-1)out("yes");
        else if(x==-2)out("no");
        else out(x);
    }
}

Compilation message (stderr)

servers.cpp: In lambda function:
servers.cpp:161:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  161 |         for(ll x:tmp)bit.add(x,-1);for(ll x:tmp2)ok[x]=false;
      |         ^~~
servers.cpp:161:36: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  161 |         for(ll x:tmp)bit.add(x,-1);for(ll x:tmp2)ok[x]=false;
      |                                    ^~~

• 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