Submission #948437

#	Time	Username	Problem	Language	Result	Execution time	Memory
948437		hotboy2703	Tourism (JOI23_tourism)	C++14	0 / 100	166 ms	37980 KiB

tourism

#include<bits/stdc++.h>
using ll = long long;
#define pll pair <ll,ll>
#define fi first
#define se second
#define sz(a) (ll((a).size()))
#define BIT(mask,i) (((mask) >> (i))&1)
#define MASK(i) (1LL << (i))
#define MP make_pair
using namespace std;
const ll bl_size = 300;
ll n,m,q;
const ll MAXN = 1e5;
const ll MAXK = 17;
ll c[MAXN+100];
struct query{
    ll l,r,id;
};
query all[MAXN+100];
ll ans[MAXN+100];
vector <ll> g[MAXN+100];
ll in[MAXN+100],out[MAXN+100];
ll timeDFS;
ll depth[MAXN+100];
ll sp[MAXK][MAXN+100];
bool anc(ll x,ll y){
    return in[x] <= in[y] && in[y] <= out[x];
}
ll lca(ll x,ll y){
    for (ll j = MAXK - 1;j >= 0;j --){
        if (!anc(sp[j][x],y))x = sp[j][x];
    }
    if (!anc(x,y))x=sp[0][x];
    return x;
}
void dfs(ll u,ll p){
    in[u] = ++timeDFS;
    sp[0][u] = p;
    depth[u] = depth[p] + 1;
    for (auto v:g[u]){
        if (v==p)continue;
        dfs(v,u);
    }
    out[u] = timeDFS;
}
int main(){
    ios_base::sync_with_stdio(0);cin.tie(nullptr);cout.tie(nullptr);
    cin>>n>>m>>q;
    for (ll i = 1;i < n;i ++){
        ll u,v;
        cin>>u>>v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    dfs(1,1);
    for (ll j = 1;j < MAXK;j ++){
        for (ll i = 1;i <= n;i ++){
            sp[j][i] = sp[j-1][sp[j-1][i]];
        }
    }
    for (ll i = 1;i <= m;i ++)cin>>c[i];
    for (ll i = 1;i <= q;i ++){
        cin>>all[i].l>>all[i].r;
        all[i].id = i;
    }
    sort(all+1,all+1+q,[](query x,query y){
            x.l /= bl_size;
            y.l /= bl_size;
            if (x.l != y.l)return x.l<y.l;
            else{
                if ((x.l)&1)return x.r < y.r;
                else return x.r > y.r;
            }
         });
    ll cur_l = 1,cur_r = 1;
    set <pll> tree({MP(in[c[1]],c[1])});
    ll res = 1;
    auto eval = [&](ll x) -> ll{
        //evaluate if insert x
        ll root = lca((*tree.begin()).se,(*tree.rbegin()).se);
        if (anc(root,x)){
            auto nxt = tree.lower_bound(MP(in[x],x));
            if (nxt == tree.end()){
                nxt = prev(nxt);
            }
            if (anc(x,(*nxt).se))return 0;
            else {
                ll lca1 = lca(x,(*nxt).se);
                ll lca2 = 1;
                if (nxt != tree.begin())lca2 = lca(x,(*prev(nxt)).se);
                if (depth[lca2] > depth[lca1])lca1 = lca2;
                return depth[x] - depth[lca1];
            }
        }
        else{
            return depth[x] + depth[root] - 2 * depth[lca(root,x)];
        }
    };
    auto add = [&](ll x){
        res += eval(x);
        tree.insert(MP(in[x],x));
    };
    auto del = [&](ll x){
        tree.erase(MP(in[x],x));
        res -= eval(x);
    };
    for (ll i = 1;i <= q;i ++){
        ll l = all[i].l,r = all[i].r;
        while (cur_r < r){
            cur_r++;
            add(c[cur_r]);
            //add cur_r
        }
        while (cur_l > l){
            cur_l--;
            add(c[cur_l]);
            //add cur_l
        }
        while (cur_r > r){
            //
            del(c[cur_r]);
            cur_r--;
        }
        while (cur_l < l){
            //
            del(c[cur_l]);
            cur_l++;
        }
        ans[all[i].id] = res;
    }
    for (ll i = 1;i <= q;i ++)cout<<ans[i]<<'\n';
//    cout<<'\n';
    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 5
• Subtask 3: 0 / 7
• Subtask 4: 0 / 18
• Subtask 5: 0 / 24
• Subtask 6: 0 / 41