Submission #342010

#	Time	Username	Problem	Language	Result	Execution time	Memory
342010		wwdd	Birthday gift (IZhO18_treearray)	C++14	100 / 100	1233 ms	79072 KiB

treearray

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> ii;
const int MN = 200200;
const int LOG = 18;
vvi g;
int pa[MN][LOG];
int dord;
int en[MN],ex[MN];
void dfs(int u, int p) {
	en[u] = dord;dord++;
	pa[u][0] = p;
	for(int i=0;i<g[u].size();i++) {
		int v = g[u][i];
		if(v == p) {continue;}
		dfs(v,u);
	}
	ex[u] = dord;dord++;
}
void proc() {
	dord = 0;
	dfs(0,0);
	for(int j=1;j<LOG;j++) {
		for(int i=0;i<g.size();i++) {
			pa[i][j] = pa[pa[i][j-1]][j-1];
		}
	}
}
bool anc(int a, int b) {
	return en[a] <= en[b] && ex[a] >= ex[b];
}
int lca(int a, int b) {
	if(anc(a,b)) {return a;}
	if(anc(b,a)) {return b;}
	for(int i=LOG-1;i>=0;i--) {
		if(!anc(pa[a][i],b)) {a = pa[a][i];}
	}
	return pa[a][0];
}
vi wa;
set<int> sa[MN],da[MN];
void up(int idx, int u) {
	sa[wa[idx]].erase(idx);
	if(idx < wa.size()-1) {
		int ol = lca(wa[idx],wa[idx+1]);
		da[ol].erase(idx);
		int nl = lca(u,wa[idx+1]);
		da[nl].insert(idx);
	}
	if(idx > 0) {
		int ol = lca(wa[idx-1],wa[idx]);
		da[ol].erase(idx-1);
		int nl = lca(u,wa[idx-1]);
		da[nl].insert(idx-1);
	}
	wa[idx] = u;
	sa[u].insert(idx);
}
int main() {
	ios::sync_with_stdio(0);cin.tie(0);
	ll n,m,q;
	cin >> n >> m >> q;
	g.assign(n,vi());
	for(int i=1;i<n;i++) {
		ll a,b;
		cin >> a >> b;
		a--;b--;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	proc();
	for(int i=0;i<m;i++) {
		ll t;
		cin >> t;
		t--;
		wa.push_back(t);
		sa[t].insert(i);
	}
	for(int i=0;i<m-1;i++) {
		da[(lca(wa[i],wa[i+1]))].insert(i);
	}
	while(q--) {
		ll op;
		cin >> op;
		if(op == 1) {
			ll id, u;
			cin >> id >> u;
			id--;u--;
			up(id,u);
		} else {
			ll l,r,u;
			cin >> l >> r >> u;
			l--;r--;u--;
			auto sal = (sa[u].lower_bound(l));
			auto dal = (da[u].lower_bound(l));
			ii ans = {-1,-1};
			if(sal != sa[u].end() && *sal <= r) {
				ll re = *sal;
				ans = {re+1,re+1};
			}
			if(dal != da[u].end() && *dal <= r-1) {
				ll re = *dal;
				ans = {re+1,re+2};
			}
			cout << ans.first << " " << ans.second << '\n';
		}
	}
}

Compilation message (stderr)

treearray.cpp: In function 'void dfs(int, int)':
treearray.cpp:16:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |  for(int i=0;i<g[u].size();i++) {
      |              ~^~~~~~~~~~~~
treearray.cpp: In function 'void proc()':
treearray.cpp:27:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |   for(int i=0;i<g.size();i++) {
      |               ~^~~~~~~~~
treearray.cpp: In function 'void up(int, int)':
treearray.cpp:47:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |  if(idx < wa.size()-1) {
      |     ~~~~^~~~~~~~~~~~~

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