Submission #1054960

#	Time	Username	Problem	Language	Result	Execution time	Memory
1054960		hotboy2703	Prize (CEOI22_prize)	C++17	0 / 100	699 ms	286424 KiB

Main

#include<bits/stdc++.h>
using ll = int;
using namespace std;
#define pll pair <ll,ll>
#define fi first
#define se second
#define MP make_pair
#define sz(a) (ll((a).size()))
#define BIT(mask,i) (((mask) >> (i))&1)
#define MASK(i) (1LL << (i))	
const ll MAXN = 5e5+100;
const ll MAXK = 19;
ll n,k,q,t;
struct tree{
	vector <ll> g[MAXN];
	ll depth[MAXN];
	ll sp[MAXN][MAXK];
	vector <pll> adj[MAXN];
	ll dp[MAXN];
	vector <ll> choose;
	ll in[MAXN],timeDFS;
	void dfs(ll u,ll p){
		sp[u][0] = p;
		in[u] = ++timeDFS;
		for (ll j = 1;j < MAXK;j ++){
			sp[u][j] = sp[sp[u][j-1]][j-1];
		}
		depth[u] = depth[p]+1;
		choose.push_back(u);
		for (auto v:g[u]){
			if (v==p)continue;
			dfs(v,u);
		}
	}
	ll lca(ll u,ll v){
		if (depth[u] > depth[v])swap(u,v);
		for (ll j = MAXK-1;j >= 0;j --){
			if (depth[sp[v][j]] >= depth[u])v = sp[v][j];
		}
		if (u==v)return u;
		for (ll j = MAXK-1;j >= 0;j--){
			if (sp[v][j] != sp[u][j])u = sp[u][j],v = sp[v][j];
		}
		return u;
	}
	ll root=-1;
	void add(ll u,ll v,ll wu,ll wv){
		ll LCA = lca(u,v);
		if (root==-1||depth[LCA]<depth[root])root=LCA;
		adj[LCA].push_back(MP(u,wu));
		adj[u].push_back(MP(LCA,wu));
		adj[LCA].push_back(MP(v,wv));
		adj[v].push_back(MP(LCA,wv));
	}
	void solve(){
		// for (ll i = 1;i <= n;i ++){
		// 	if (dp[i] == 0){
				queue <ll> q;
				q.push(root);
				while (!q.empty()){
					ll u = q.front();
					q.pop();
					for (auto [v,w]:adj[u]){
						if (v != u && dp[v] == 0){
							dp[v] = dp[u] + (depth[u] > depth[v] ? -1 : + 1) * w;
							q.push(v);
						}
					}
				}
			// }
		// }
	}
	ll query(ll u,ll v){
		ll LCA = lca(u,v);
		return dp[u] + dp[v] - dp[LCA]*2;
	}
} a1,a2;
int main(){
	ios_base::sync_with_stdio(0);cin.tie(nullptr);
	cin>>n>>k>>q>>t;
	ll r1,r2;
	for (ll i = 1;i <= n;i ++){
		ll x;
		cin>>x;
		if (x!=-1){
			a1.g[x].push_back(i);
			a1.g[i].push_back(x);
		}
		else r1 = i;
	}
	// cout<<"OK"<<endl;
	for (ll i = 1;i <= n;i ++){

		ll x;
		cin>>x;
		if (x!=-1){
			a2.g[x].push_back(i);
			a2.g[i].push_back(x);
		}
		else r2 = i;
	}
	// cout<<"OK"<<endl;
	a1.dfs(r1,r1);
	a2.dfs(r2,r2);
	// cout<<"WAT"<<endl;
	// return 0;
	vector <ll> c = a1.choose;
	c.resize(k);
	sort(c.begin(),c.end(),[](ll x,ll y){return a2.in[x] < a2.in[y];});
	for (auto x:c)cout<<x<<' ';
	cout<<'\n';
	for (ll j = 0;j + 1 < sz(c);j ++)cout<<"? "<<c[j]<<' '<<c[j+1]<<'\n';
	cout<<'!'<<endl;
	for (ll j = 0;j + 1 < sz(c);j ++){
		ll u1,v1,u2,v2;
		cin>>u1>>v1>>u2>>v2;
		a1.add(c[j],c[j+1],u1,v1);
		a2.add(c[j],c[j+1],u2,v2);
	}
	// return 0;
	a1.solve(),a2.solve();
	// return 0;
	while (t--){
		ll x,y;
		cin>>x>>y;
		cout<<a1.query(x,y)<<' '<<a2.query(x,y)<<'\n';
	}
	cout.flush();
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:103:8: warning: 'r1' may be used uninitialized in this function [-Wmaybe-uninitialized]
  103 |  a1.dfs(r1,r1);
      |  ~~~~~~^~~~~~~
Main.cpp:104:8: warning: 'r2' may be used uninitialized in this function [-Wmaybe-uninitialized]
  104 |  a2.dfs(r2,r2);
      |  ~~~~~~^~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 25
• Subtask 3: 0 / 19
• Subtask 4: 0 / 22
• Subtask 5: 0 / 24