Submission #146997

#	Time	Username	Problem	Language	Result	Execution time	Memory
146997		qkxwsm	Toll (APIO13_toll)	C++14	0 / 100	28 ms	28664 KiB

toll

#include <bits/stdc++.h>

using namespace std;

template<class T, class U>
void ckmin(T &a, U b)
{
	if (a > b) a = b;
}
template<class T, class U>
void ckmax(T &a, U b)
{
	if (a < b) a = b;
}

#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
#define SZ(x) ((int) ((x).size()))
#define ALL(x) (x).begin(), (x).end()
#define MAXN 300013

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;

int N, M, K;
vector<pair<ll, pii> > edges;
vi edge[MAXN], edge1[MAXN];
ll arr[MAXN];
vi nodes;
map<int, ll> cost[MAXN];
vpi cand;
int dsu[MAXN];
bitset<MAXN> flag, take, imp;
int parent[MAXN];
ll dp[MAXN], subtree[MAXN];
ll ans;

int get(int u)
{
	return (u == dsu[u] ? u : dsu[u] = get(dsu[u]));
}
bool merge(int u, int v)
{
	u = get(u); v = get(v);
	if (u == v) return false;
	dsu[u] = v;
	return true;
}
void dfs(int u, int p)
{
	subtree[u] = arr[u];
	for (int v : edge1[u])
	{
		if (v == p) continue;
		parent[v] = u;
		dfs(v, u);
		subtree[u] += subtree[v];
	}
	return;
}

int32_t main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin >> N >> M >> K;
	flag[0] = true;
	FOR(i, 0, M)
	{
		int u, v; ll d;
		cin >> u >> v >> d; u--; v--; if (u > v) swap(u, v);
		edges.PB({d, {u, v}});
	}
	FOR(i, 0, K)
	{
		int u, v; cin >> u >> v; u--; v--;
		cand.PB({u, v});
		flag[u] = true;
		flag[v] = true;
	}
	FOR(i, 0, N)
	{
		cin >> arr[i];
		dsu[i] = i;
	}
	sort(ALL(edges));
	for (auto e : edges)
	{
		// cerr << "HI\n";
		int u = e.se.fi, v = e.se.se; ll d = e.fi;
		if (merge(u, v))
		{
			cost[u][v] = d;
			cost[v][u] = d;
			edge[u].PB(v);
			edge[v].PB(u);
			// cerr << u << ' ' << v << ' ' << cost[u][v] << endl;
		}
	}
	flag[0] = true;
	FOR(i, 0, N) dsu[i] = i;
	FOR(u, 0, N)
	{
		if (flag[u]) continue;
		for (int v : edge[u])
		{
			if (flag[v]) continue;
			merge(u, v);
		}
	}
	FOR(i, 0, N)
	{
		if (get(i) == i) nodes.PB(i);
		else
		{
			arr[get(i)] += arr[i];
		}
	}
	edges.clear();
	FOR(u, 0, N)
	{
		for (int v : edge[u])
		{
			if ((!flag[u] && !flag[v]) || u > v) continue;
			edges.PB({cost[u][v], {get(u), get(v)}});
		}
	}
	sort(ALL(edges));
	dfs(0, N);
	M = SZ(edges);
	parent[0] = N;
	FOR(i, 0, (1 << K))
	{
		for (int x : nodes)
		{
			dsu[x] = x;
			edge1[x].clear();
			dp[x] = 0;
			imp[x] = false;
		}
		FOR(j, 0, K)
		{
			if (!(i & (1 << j))) continue;
			int u = cand[j].fi, v = cand[j].se;
			merge(u, v);
		}
		FOR(j, 0, SZ(edges))
		{
			int u = edges[j].se.fi, v = edges[j].se.se;
			take[j] = merge(u, v);
		}
		FOR(j, 0, K)
		{
			if (!(i & (1 << j))) continue;
			int u = cand[j].fi, v = cand[j].se;
			edge1[u].PB(v);
			edge1[v].PB(u);
		}
		FOR(j, 0, SZ(edges))
		{
			if (!take[j]) continue;
			int u = edges[j].se.fi, v = edges[j].se.se;
			edge1[u].PB(v);
			edge1[v].PB(u);
		}
		dfs(0, N);
		FOR(j, 0, K)
		{
			if (!(i & (1 << j))) continue;
			int u = cand[j].fi, v = cand[j].se;
			if (v == parent[u]) continue;
			imp[v] = true;
		}
		FORD(j, SZ(edges), 0)
		{
			if (take[j]) continue;
			int u = edges[j].se.fi, v = edges[j].se.se; ll d = edges[j].fi;
			//everything on the path u...v gets capped to
			vi pu, pv;
			while(u != 0)
			{
				pu.PB(u);
				u = parent[u];
			}
			while(v != 0)
			{
				pv.PB(v);
				v = parent[v];
			}
			while(pu.back() == pv.back())
			{
				pu.pop_back(); pv.pop_back();
			}
			for (int x : pu) dp[x] = d;
			for (int x : pv) dp[x] = d;
		}
		ll res = 0;
		for (int x : nodes)
		{
			if (!imp[x]) continue;
			res += subtree[x] * dp[x];
		}
		ckmax(ans, res);
	}
	cout << ans << '\n';
	return 0;
}

• Subtask 1: 0 / 16
• Subtask 2: 0 / 18
• Subtask 3: 0 / 22
• Subtask 4: 0 / 22
• Subtask 5: 0 / 22