Submission #880909

#	Time	Username	Problem	Language	Result	Execution time	Memory
880909		tigran	Birthday gift (IZhO18_treearray)	C++17	100 / 100	1076 ms	76628 KiB

treearray

#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <unordered_set>
#include <cstdlib>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <algorithm>
#include <bitset>
#include <queue>
#include <unordered_map>
#include <fstream>
#include <random>
typedef unsigned long long ull;
typedef long long ll;
using namespace std;
vector <vector<int>> G;
const int N = 2e5 + 10;
int a[N];
int dp[N][20];
int depth[N];
set <int> f1[N];
set <int> f2[N];
void dfs(int v, int p) {
	depth[v] = depth[p] + 1;
	dp[v][0] = p;
	for (int j = 1; j < 20; j++) {
		dp[v][j] = dp[dp[v][j - 1]][j - 1];
	}
	for (auto it : G[v]) {
		if (it == p) continue;
		dfs(it, v);
	}
}
int find_lca(int a, int b) {
	if (depth[a] < depth[b]) swap(a, b);
	int k = depth[a] - depth[b];
	for (int i = 0; i < 20; i++) {
		if (k & (1 << i)) {
			a = dp[a][i];
		}
	}
	if (a == b) return a;
	for (int i = 19; i >= 0; i--) {
		if (dp[a][i] != dp[b][i]) {
			a = dp[a][i];
			b = dp[b][i];
		}
	}
	return dp[a][0];
}
int main() {
	int n, m, q;
	cin >> n >> m >> q;
	G.resize(n + 1);
	for (int i = 1; i < n; i++) {
		int a, b;
		cin >> a >> b;
		G[a].push_back(b);
		G[b].push_back(a);
	}
	dfs(1, 1);
	for (int i = 1; i <= m; i++) {
		cin >> a[i];
		f1[a[i]].insert(i);
	}
	for (int i = 1; i <= m - 1; i++) {
		f2[find_lca(a[i], a[i + 1])].insert(i);
	}
	while (q--) {
		int type;
		cin >> type;
		if (type == 1) {
			int pos, val;
			cin >> pos >> val;
			f1[a[pos]].erase(pos);
			f1[val].insert(pos);
			if (pos != 1) {
				f2[find_lca(a[pos - 1], a[pos])].erase(pos - 1);
				f2[find_lca(a[pos - 1], val)].insert(pos - 1);
			}
			if (pos != n) {
				f2[find_lca(a[pos], a[pos + 1])].erase(pos);
				f2[find_lca(val, a[pos + 1])].insert(pos);
			}
			a[pos] = val;
		}
		else {
			int l, r, v;
			cin >> l >> r >> v;
			auto it = f1[v].lower_bound(l);
			if (it != f1[v].end() && *it <= r) {
				cout << *it << " " << *it << "\n";
				continue;
			}
			auto w = f2[v].lower_bound(l);
			if (w != f2[v].end() && *w < r) {
				cout << *w << " " << *w + 1 << "\n";
				continue;
			}
			cout << -1 << " " << -1 << "\n";
		}
	}
}

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