Submission #1164024

#	Time	Username	Problem	Language	Result	Execution time	Memory
1164024		omar1312	Birthday gift (IZhO18_treearray)	C++20	0 / 100	3 ms	5188 KiB

treearray

#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_multiset;
#define ll long long
#define pb push_back
#define all(x) x.begin(), x.end()
const int mod = 1000000007;
const int N = 200005;
ll a[N+2], dp[N+2], sp[N+2][32], dep[N+2], par[N+2];
vector<int> adj[N+2];
void dfs(int n, int _par, int d){
    dep[n] = d;
    par[n] = _par;
    for(auto i : adj[n]){
        if(i == _par)continue;
        dfs(i, n, d + 1);
    }
}
ll lca(ll u, ll v){
    if(u && !v)return u;
    else if(!u && v)return v;
    else if(!u && !v)return 0;
    if(dep[u] < dep[v])swap(u, v);
    if(dep[u] != dep[v]){
        ll delta = dep[u] - dep[v];
        for(int j = 0; j < 30; j++){
            if((delta >> j) & 1){
                u = sp[u][j];
            }
        }
    }
    if(u == v)return u;
    for(int j = 0; j < 30; j++){
        if(sp[u][j] != sp[v][j]){
            u = sp[u][j];
            v = sp[v][j];
        }
    }
    return par[u];
}
struct Segtree{
    vector<ll> t;
    ll off = 1;
    Segtree(int n){
        while(off < n)off <<= 1;
        t.resize(2 * off, 0);
        for(int i = 0; i < n; i++){
            t[i + off] = a[i];
        }
        for(int i = off - 1; i >= 0; i--){
            t[i] = lca(t[i * 2], t[i * 2 + 1]);
        }
    }
    ll query(ll n, ll ql, ll qh, ll nl, ll nh){
        if(ql > nh || qh < nl)return 0;
        if(ql <= nl && qh >= nh)return t[n];
        ll m = (nl + nh) / 2;
        return lca(query(n * 2, ql, qh, nl, m), query(n * 2 + 1, ql, qh, m + 1, nh));
    }
    void update(ll u, ll v){
        a[u] = v;
        t[u += off] = v;
        while(u >>= 1)t[u] = lca(t[u * 2], t[u * 2 + 1]);
    }
};
void solve(){
    int n, m, q;
    cin>>n>>m>>q;
    for(int i = 0; i < n - 1; i++){
        int u, v;
        cin>>u>>v;
        adj[u].pb(v);
        adj[v].pb(u);
    }
    for(int i = 0; i < m; i++){
        cin>>a[i];
    }
    dfs(1, 0, 1);
    for(int i = 1; i <= n; i++){
        sp[i][0] = par[i];
    }
    for(int j = 1; j < 30; j++){
        for(int i = 1; i <= n; i++){
            sp[i][j] = sp[sp[i][j - 1]][j - 1];
        }
    }
    Segtree segtree(m);
    while(q--){
        int t;
        cin>>t;
        if(t == 1){
            int u, v;
            cin>>u>>v;
            segtree.update(--u, v);
        }
        else{
            int ql, qh, v, ansL = -1, ansR = -1;
            cin>>ql>>qh>>v;
            --ql, --qh;
            for(int i = ql; i <= qh; i++){
                int l = i, r = qh;
                while(l <= r){
                    ll mid = (l + r) / 2;
                    ll ans = segtree.query(1, i, mid, 0, segtree.off - 1);
                    if(ans == v){
                        ansL = i, ansR = mid;
                        break;
                    }
                    if(dep[ans] > dep[v]){
                        l = mid + 1;
                    }
                    else r = mid - 1;
                }
                if(~ansL && ~ansR){
                    cout<<ansL + 1<<' '<<ansR + 1<<'\n';
                    goto done;
                }
            }
            cout<<-1<<' '<<-1<<'\n';
            done:;
        }
    }
}
int main(){
cin.tie(0)->sync_with_stdio(0);
    int tt = 1;
    //cin>>tt;
    while(tt--){
        solve();
        // cout<<'\n';
    }
}

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