Submission #500801

#	Time	Username	Problem	Language	Result	Execution time	Memory
500801		pragmatist	Birthday gift (IZhO18_treearray)	C++17	56 / 100	4046 ms	56344 KiB

treearray

#include <bits/stdc++.h>                            
 
#define pb push_back
#define sz(v) (int)v.size()
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define x first
#define y second
#define int long long
#define nl "\n"
 
using namespace std;

typedef long long ll;
typedef pair<long long, long long> pll;
typedef pair <ll, ll> pii;

const int N = (int)2e5 + 7;
const int M = (int)7e6 + 7;
const ll MOD = (ll)1e9 + 7;                    
const int inf = (int)1e9 + 7;
const ll INF = (ll)3e18 + 7;

pii dir[] = {{-1, -1}, {1, 1}, {-1, 1}, {1, -1}};

int n, m, q, a[N], t[4*N], leaf;
int timer, tin[N], tout[N], up[N][19];
vector<int> g[N];

void calc(int v, int pr) {
	up[v][0] = pr;
	tin[v] = ++timer;
	for(int i = 1; i <= 18; ++i) {
		up[v][i] = up[up[v][i-1]][i-1];
	}
	for(auto to : g[v]) {
		if(to != pr) {
			calc(to, v);
		}
	}	
	tout[v] = ++timer;
}

bool is_parent(int u, int v) {
	return tin[u] <= tin[v] && tout[u] >= tout[v];
}

int lca(int u, int v) {
	if(u == -1) return v;
	if(v == -1) return u;
	if(is_parent(u, v)) return u;
	if(is_parent(v, u)) return v;
	for(int i = 18; i >= 0; --i) {
		if(!is_parent(up[u][i], v)) {
			u = up[u][i];
		}
	}
	return up[u][0];
}

void build(int v, int tl, int tr) {
	if(tl == tr) {
		t[v] = a[tl];
		return;
	}
	int mid = (tl + tr) >> 1;
	build(v * 2, tl, mid);
	build(v * 2 + 1, mid + 1, tr);
	t[v] = lca(t[v * 2], t[v * 2 + 1]);
}

void upd(int v, int tl, int tr, int id, int x) {
	if(tl == tr) {
		t[v] = x;
		return;
	}
	int mid = (tl + tr) >> 1;
	if(id <= mid)
		upd(v * 2, tl, mid, id, x);
	else
		upd(v * 2 + 1, mid + 1, tr, id, x);
	t[v] = lca(t[v * 2], t[v * 2 + 1]);
}

int get(int v, int tl, int tr, int l, int r) {
	if(tl >= l && tr <= r)
		return t[v];
	if(tl > r || l > tr)
		return -1;
	int mid = (tl + tr) >> 1;
	return lca(get(v * 2, tl, mid, l, r), get(v * 2 + 1, mid + 1, tr, l, r));
}

void solve() { 
	cin >> n >> m >> q;
	for(int i = 1; i < n; ++i) {
		int u, v;
		cin >> u >> v;
		g[u].pb(v);
		g[v].pb(u);
	}
	for(int i = 1; i <= m; ++i) cin >> a[i];
	calc(1, 1);
	build(1, 1, m);            	
	while(q--) {
		char tp;
		cin >> tp;
		int l, r, v;
		if(tp == '1') {
			cin >> l >> r;
			upd(1, 1, m, l, r);
		} else {
			cin >> l >> r >> v;
			int a = -1, b = -1;
			for(int i = l; i <= r && a == -1; ++i) {
				int L = i, R = r, res = -1;
				while(L <= R) {
					int mid = (L + R) >> 1;
					int x = get(1, 1, m, i, mid);
					if(x == v) {
						a = i;
						b = mid;
						break;
					}
					if(is_parent(x, v)) {
						res = mid;
						R = mid - 1;
					} else 
						L = mid + 1;
				}				
			}
			cout << a << ' ' << b << nl;			
		}
	} 	
}

signed main() {                   
	ios_base::sync_with_stdio(NULL);
    cin.tie(0);
    cout.tie(0);
   	int test = 1;
	//cin >> test;
	for(int i = 1; i <= test; ++i) {
        //cout << "Case " << i << ": ";
        solve();
    }
    return 0;
}
/*
5 4 4
1 2
3 1
3 4
5 3
4 5 2 3
2 1 3 1
1 3 5
2 3 4 5
2 1 3 1
*/

Compilation message (stderr)

treearray.cpp: In function 'void solve()':
treearray.cpp:116:23: warning: variable 'res' set but not used [-Wunused-but-set-variable]
  116 |     int L = i, R = r, res = -1;
      |                       ^~~

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 0 / 44