Submission #894591

#	Time	Username	Problem	Language	Result	Execution time	Memory
894591		zeta7532	Birthday gift (IZhO18_treearray)	C++17	100 / 100	1900 ms	82572 KiB

treearray

#include <bits/stdc++.h>
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
using ll = long long;
const ll mod = 998244353;
#define fi first
#define se second
#define rep(i,n) for(ll i=0;i<n;i++)
#define all(x) x.begin(),x.end()
#define faster ios::sync_with_stdio(false);cin.tie(nullptr)
 
using Graph = vector<vector<ll>>;
 
struct LCA{
    vector<vector<ll>> par;
    vector<ll> dis;
    LCA(const Graph &G,ll root=0){init (G,root);}
    void init(const Graph &G,ll root=0){
        ll v=G.size();
        ll k=1;
        while((1<<k)<v) k++;
        par.assign(k,vector<ll>(v,-1));
        dis.assign(v,-1);
        dfs(G,root,-1,0);
        for(ll i=0;i+1<k;i++){
            for(ll j=0;j<v;j++){
                if(par[i][j]<0) par[i+1][j]=-1;
                else par[i+1][j]=par[i][par[i][j]];
            }
        }
    }
    void dfs(const Graph &G,ll v,ll p,ll d){
        par[0][v]=p;
        dis[v]=d;
        for(ll nv:G[v]){
            if(nv!=p) dfs(G,nv,v,d+1);
        }
    }
    ll query(ll u,ll v){
        if(dis[u]<dis[v]) swap(u,v);
        ll K=par.size();
        for(ll k=0;k<K;k++){
            if((dis[u]-dis[v])>>k&1){
                u=par[k][u];
            }
        }
        if(u==v) return u;
        for(ll k=K-1;k>=0;k--){
            if(par[k][u]!=par[k][v]){
                u=par[k][u];
                v=par[k][v];
            }
        }
        return par[0][u];
    }
    ll get_dis(ll u,ll v){return dis[u]+dis[v]-2*dis[query(u,v)];}
};
 
int main() {
    ll N,M,Q;
    cin >> N >> M >> Q;
    Graph G(N);
    rep(i,N-1){
        ll u,v;
        cin >> u >> v;
        u--,v--;
        G[u].push_back(v);
        G[v].push_back(u);
    }
    auto lca=LCA(G);
    vector<ll> A(M);
    rep(i,M) cin >> A[i],A[i]--;
    set<pair<ll,pair<ll,ll>>> s;
    rep(i,M) s.insert({A[i],{i,i}});
    rep(i,M-1) s.insert({lca.query(A[i],A[i+1]),{i,i+1}});
    s.insert({M,{M,M}});
    while(Q--){
        ll q;
        cin >> q;
        if(q==1){
            ll i,v;
            cin >> i >> v;
            i--,v--;
            s.erase({A[i],{i,i}});
            if(i>0) s.erase({lca.query(A[i-1],A[i]),{i-1,i}});
            if(i<M-1) s.erase({lca.query(A[i],A[i+1]),{i,i+1}});
            A[i]=v;
            s.insert({A[i],{i,i}});
            if(i>0) s.insert({lca.query(A[i-1],A[i]),{i-1,i}});
            if(i<M-1) s.insert({lca.query(A[i],A[i+1]),{i,i+1}});
        }
        if(q==2){
            ll l,r,v;
            cin >> l >> r >> v;
            l--,r--,v--;
            auto it=*s.lower_bound({v,{l,l}});
            if(it.fi==v&&it.se.se<=r){
                cout << it.se.fi+1 << " " << it.se.se+1 << endl;
            }else cout << -1 << " " << -1 << endl;
        }
    }
    return 0;
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44