Submission #851022

#	Time	Username	Problem	Language	Result	Execution time	Memory
851022		wakandaaa	Birthday gift (IZhO18_treearray)	C++17	100 / 100	1142 ms	191336 KiB

treearray

#include <bits/stdc++.h>

using namespace std;

#define file ""

#define mp make_pair
#define fi first
#define se second
#define all(x) x.begin(), x.end()

#define getbit(x, i) (((x) >> (i)) & 1)
#define bit(x) (1LL << (x))
#define popcount __builtin_popcountll

mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r) {
    return l + rd() % (r - l + 1);
}

const int N = 1e6 + 5;
const int mod = (int)1e9 + 7; // 998244353;
const int lg = 25; // lg + 1
const int oo = 1e9;
const long long ooo = 1e18;

template<class X, class Y> bool mini(X &a, Y b) {
    return a > b ? (a = b, true) : false;
}
template<class X, class Y> bool maxi(X &a, Y b) {
    return a < b ? (a = b, true) : false;
}
void add(int &a, int b) {
    a += b;
    if (a >= mod) a -= mod;
    if (a < 0) a += mod;
}

int n, m, q;
vector<int> adj[N];
int h[N], par[N][lg + 1];
int a[N];
set<int> pos[N], f[N];

void dfs(int u, int p) {
	par[u][0] = p;
	for (int i = 1; i <= lg; ++i) par[u][i] = par[par[u][i - 1]][i - 1];
	for (int v : adj[u]) if (v != p) {
		h[v] = h[u] + 1;
		dfs(v, u);
	}
}
int lca(int u, int v) {
	if (h[u] < h[v]) swap(u, v);
	for (int i = lg; i >= 0; --i) if (h[par[u][i]] >= h[v]) u = par[u][i];
	if (u == v) return u;
	for (int i = lg; i >= 0; --i) if (par[u][i] != par[v][i]) {
		u = par[u][i];
		v = par[v][i];
	}
	return par[u][0];
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    // freopen(file".inp", "r", stdin);
    // freopen(file".out", "w", stdout);

    cin >> n >> m >> q;
    for (int i = 1; i < n; ++i) {
    	int u, v;
    	cin >> u >> v;
    	adj[u].push_back(v);
    	adj[v].push_back(u);
    }

    h[0] = -1;
    dfs(1, 0);

    for (int i = 1; i <= m; ++i) {
    	cin >> a[i];
    	pos[a[i]].insert(i);
    }
    for (int i = 2; i <= m; ++i) {
    	f[lca(a[i - 1], a[i])].insert(i - 1);
    }

    while (q--) {
    	int op;
    	cin >> op;
    	if (op == 1) {
    		int id, v;
    		cin >> id >> v;
    		if (id > 1) f[lca(a[id - 1], a[id])].erase(id - 1);
    		if (id < m) f[lca(a[id], a[id + 1])].erase(id);
    		pos[a[id]].erase(id);
    		a[id] = v;
    		if (id > 1) f[lca(a[id - 1], a[id])].insert(id - 1);
    		if (id < m) f[lca(a[id], a[id + 1])].insert(id);
    		pos[a[id]].insert(id);
    	}
    	else {
    		int l, r, v;
    		cin >> l >> r >> v;
    		auto it = pos[v].lower_bound(l);
    		if (it != pos[v].end() && *it <= r) {
    			cout << *it << ' ' << *it << '\n';
    		}
    		else {
    			it = f[v].lower_bound(l);
    			if (it != f[v].end() && *it + 1 <= r) {
    				cout << *it << ' ' << *it + 1 << '\n';
    			}
    			else {
    				cout << -1 << ' ' << -1 << '\n';
    			}
    		}
    	}
    }

    return 0;
}

/*

*/

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