Submission #1131328

#	Time	Username	Problem	Language	Result	Execution time	Memory
1131328		Nonoze	Bridges (APIO19_bridges)	C++20	59 / 100	3094 ms	21148 KiB

bridges

/*
*	Author: Nonoze
*	Created: Tuesday 31/12/2024
*/
#include <bits/stdc++.h>
using namespace std;

#ifndef IN_LOCAL
	#define dbg(...)
#endif

// #define cout cerr << "OUT: "
#define endl '\n'
#define endlfl '\n' << flush
#define quit(x) return (void)(cout << x << endl)

template<typename T> void read(T& x) { cin >> x;}
template<typename T1, typename T2> void read(pair<T1, T2>& p) { read(p.first), read(p.second);}
template<typename T> void read(vector<T>& v) { for (auto& x : v) read(x); }
template<typename T1, typename T2> void read(T1& x, T2& y) { read(x), read(y); }
template<typename T1, typename T2, typename T3> void read(T1& x, T2& y, T3& z) { read(x), read(y), read(z); }
template<typename T1, typename T2, typename T3, typename T4> void read(T1& x, T2& y, T3& z, T4& zz) { read(x), read(y), read(z), read(zz); }
template<typename T> void print(vector<T>& v) { for (auto& x : v) cout << x << ' '; cout << endl; }

#define sz(x) (int)(x.size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define make_unique(v) sort(all(v)), v.erase(unique(all(v)), (v).end())
#define pb push_back
#define mp(a, b) make_pair(a, b)
#define fi first
#define se second
#define cmin(a, b) a = min(a, b)
#define cmax(a, b) a = max(a, b)
#define YES cout << "YES" << endl
#define NO cout << "NO" << endl
#define QYES quit("YES")
#define QNO quit("NO")

#define int long long
#define double long double
const int inf = numeric_limits<int>::max() / 4;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD = 1e9+7, LOG=20;



void solve();

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int tt=1;
	// cin >> tt;
	while(tt--) solve();
	return 0;
}


vector<int> par, sz;

int getpar(int x) {
	if (x==par[x]) return x;
	return par[x]=getpar(par[x]);
}

void unite(int a, int b) {
	a=getpar(a), b=getpar(b);
	if (a==b) return;
	if (sz[a]<sz[b]) swap(a, b);
	sz[a]+=sz[b], par[b]=a;
}


int n, k, m, q;


void solve() {
	read(n, m);
	vector<vector<int>> base;
	set<vector<int>> st;
	for (int i=0; i<m; i++) {
		int u, v, w; read(u, v, w); u--, v--;
		base.pb({w, u, v});
		st.insert({w, u, v, i});
	}
	read(q); const int SQRT=650;
	vector<vector<int>> queries;
	int act=0;
	for (int t=1; t<=q; t++) {
		int o, x, y; cin >> o >> x >> y;
		queries.pb({o, x-1, y});
		if (o==2) queries.back().push_back(act++);
		if (t%SQRT==0 || t==q) {

			if (act) {
				par.clear(), sz.clear(); par.resize(n), sz.resize(n, 1); iota(all(par), 0);
				vector<bool> can(m, 1);
				for (auto u: queries) if (u[0]==1) can[u[1]]=0;
				vector<int> bridges;
				for (auto u: st) if (can[u[3]]) bridges.pb(u[3]);
				vector<int> que;
				for (int i=0; i<sz(queries); i++) {
					// if (queries[i][0]==2) que.pb({queries[i][2], queries[i][1], i, queries[i][3]});
					if (queries[i][0]==2) que.pb(i);
				}
				sort(all(que), [&](const int &a, const int &b) { return queries[a][2]>queries[b][2]; });
				vector<int> ans(act);
				vector<int> modif(m); for (int i=0; i<m; i++) modif[i]=base[i][0];
				vector<vector<int>> adj(n);
				vector<bool> visited(n, 0);
				for (auto query: que) {
					int w=queries[query][2], s=queries[query][1], i=queries[query][3];
					while (!bridges.empty() && base[bridges.back()][0]>=w) unite(base[bridges.back()][1], base[bridges.back()][2]), bridges.pop_back();
					for (int j=0; j<query; j++) {
						if (queries[j][0]==1) modif[queries[j][1]]=queries[j][2];
					}
					for (int j=0; j<sz(queries); j++) {
						if (queries[j][0]==1 && modif[queries[j][1]]>=w) {
							int u=base[queries[j][1]][1], v=base[queries[j][1]][2]; u=getpar(u), v=getpar(v);
							adj[u].pb(v), adj[v].pb(u);
						}
					}
					int res=0;
					function<void(int)> dfs=[&](int u) {
						visited[u]=1, res+=sz[u];
						for (auto v: adj[u]) if (!visited[v]) dfs(v);
					};
					dfs(getpar(s));
					ans[i]=res;

					visited[getpar(s)]=0;
					for (int j=0; j<sz(queries); j++) if (queries[j][0]==1) {
						if (modif[queries[j][1]]>=w) {
							int u=base[queries[j][1]][1], v=base[queries[j][1]][2]; u=getpar(u), v=getpar(v);
							adj[u].pop_back(), adj[v].pop_back();
							visited[u]=0, visited[v]=0;
						}
					}
					for (int j=0; j<query; j++) if (queries[j][0]==1) modif[queries[j][1]]=base[queries[j][1]][0];
				}

				for (auto u: ans) cout << u << endl;
			}


			for (auto &u: queries) if (u[0]==1) {
				st.erase({base[u[1]][0], base[u[1]][1], base[u[1]][2], u[1]});
				base[u[1]][0]=u[2];
				st.insert({base[u[1]][0], base[u[1]][1], base[u[1]][2], u[1]});
			}
			queries.clear(), act=0;
		}
	}
}

• Subtask 1: 13 / 13
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 0 / 14
• Subtask 5: 13 / 13
• Subtask 6: 0 / 27