Submission #492147

#	Time	Username	Problem	Language	Result	Execution time	Memory
492147		infertechno2	Birthday gift (IZhO18_treearray)	C++17	0 / 100	10 ms	14412 KiB

treearray

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

class nums{
public:
    ll l,r,id;
};

bool operator<(const nums& a,const nums& b){
    if(a.id==b.id){
        if(a.l==b.l){
            return a.r<b.r;
        }
        return a.l<b.l;
    }
    return a.id<b.id;
}

const ll Size=2e5+1;
ll tin[Size],height[Size],lca_tree[4*Size],visited[Size],a[Size];
set<nums> all_pairs[Size];
vector<ll> adj[Size],euler_tour;

void dfs(ll curr_node,ll depth){
    tin[curr_node]=euler_tour.size();
    height[curr_node]=depth;
    visited[curr_node]=1;
    euler_tour.push_back(curr_node);
    for(auto itr:adj[curr_node]){
        if(!visited[itr]){
            dfs(itr,depth+1);
            euler_tour.push_back(curr_node);
        }
    }
}

void build_lca(ll l,ll r,ll i){
    if(l==r){
        lca_tree[i]=euler_tour[r];
    }else{
        ll mid=(l+r)/2;
        build_lca(l,mid,i*2);
        build_lca(mid+1,r,i*2+1);
        height[lca_tree[i*2]]<height[lca_tree[i*2+1]] ? lca_tree[i]=lca_tree[i*2] : lca_tree[i]=lca_tree[i*2+1];
    }
}

ll query_lca(ll l,ll r,ll i,ll tl,ll tr){
    if(r<tl or l>tr){
        return -1;
    }
    if(l==tl and r==tr){
        return lca_tree[i];
    }else{
        ll mid=(l+r)/2;
        ll n1=query_lca(l,mid,i*2,tl,min(mid,tr));
        ll n2=query_lca(mid+1,r,i*2+1,max(tl,mid+1),tr);
        if(n1==-1)return n2;
        if(n2==-1)return n1;
        return height[n1]<height[n2] ? n1 : n2;
    }
}

ll lca(ll a,ll b){
    if(tin[a]>tin[b]) swap(a,b);
    return query_lca(0,euler_tour.size()-1,1,tin[a],tin[b]);
}

void solve(){
    ll n,m,q;
    cin>>n>>m>>q;
    for(ll i=0;i<n-1;i++){
        ll from,to;
        cin>>from>>to;
        adj[from].push_back(to);
        adj[to].push_back(from);
    }
    for(ll i=0;i<m;i++){
        cin>>a[i];
    }
    dfs(1,1);
    build_lca(0,euler_tour.size()-1,1);
    for(ll i=0;i<m-1;i++){
        ll ans=lca(a[i],a[i+1]);
        nums tmp;
        tmp.id=i;
        tmp.l=i;
        tmp.r=i+1;
        all_pairs[ans].insert(tmp);
        tmp.l=i;
        tmp.r=i;
        all_pairs[a[i]].insert(tmp);
    }
    nums tmpp;
    tmpp.l=m-1;
    tmpp.r=m-1;
    tmpp.id=m-1;
    all_pairs[a[m-1]].insert(tmpp);
    for(ll i=0;i<q;i++){
        ll type;
        cin>>type;
        if(type==1){
            ll pos,val;
            cin>>pos>>val;
            pos--;
            if(pos!=0){
                nums tmp;
                tmp.l=pos-1;
                tmp.r=pos;
                tmp.id=pos-1;
                ll lca_of_pair=lca(a[pos-1],a[pos]);
                auto found=all_pairs[lca_of_pair].find(tmp);
                if(found==all_pairs[lca_of_pair].end()){
                    cout<<"wtf"<<endl;
                    return;
                }else{
                    all_pairs[lca_of_pair].erase(tmp);
                    lca_of_pair=lca(val,a[pos-1]);
                    all_pairs[lca_of_pair].insert(tmp);
                }
            }
            tmpp.id=pos;
            tmpp.l=pos;
            tmpp.r=pos;
            all_pairs[a[pos]].erase(tmpp);
            all_pairs[val].insert(tmpp);
            if(pos!=n-1){
                nums tmp;
                tmp.l=pos;
                tmp.r=pos+1;
                tmp.id=pos;
                ll lca_of_pair=lca(a[pos],a[pos+1]);
                auto found=all_pairs[lca_of_pair].find(tmp);
                if(found==all_pairs[lca_of_pair].end()){
                    cout<<"wtf"<<endl;
                    return;
                }else{
                    all_pairs[lca_of_pair].erase(tmp);
                    lca_of_pair=lca(val,a[pos+1]);
                    all_pairs[lca_of_pair].insert(tmp);
                }
            }
            a[pos]=val;
        }
        if(type==2){
            ll l,r,v;
            cin>>l>>r>>v;
            l--; r--;
            nums tmp;
            tmp.id=r-1;
            tmp.l=n;
            tmp.r=n;
            auto itr=all_pairs[v].upper_bound(tmp);
            if(all_pairs[v].empty()){
                cout<<-1<<" "<<-1<<endl;
                continue;
            }
            itr--;
            if((*itr).id<l){
                cout<<-1<<" "<<-1<<endl;
                continue;
            }else{
                cout<<(*itr).l+1<<" "<<(*itr).r+1<<endl;
            }
        }
    }
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    ll t=1;
    while(t--){
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 18
• Subtask 3: 0 / 26
• Subtask 4: 0 / 44