Submission #393954

#	Time	Username	Problem	Language	Result	Execution time	Memory
393954		Return_0	Cities (BOI16_cities)	C++17	100 / 100	2196 ms	52792 KiB

cities

#pragma GCC optimize("Ofast,unroll-loops")
// #pragma comment(linker, "/stack:200000000")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma,tune=native")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef pair <ll, int> pll;

#ifdef SINA
#define dbg(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1> void __f(const char* name, Arg1&& arg1) { cout << name << " : " << arg1 << std::endl; }
template <typename Arg1, typename... Args> void __f (const char* names, Arg1&& arg1, Args&&... args) {
	const char* comma = strchr(names + 1, ',');cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...); }
#define dbg2(x, j, n) cout<< #x << " : "; output((j), (n), x, 1); cout.flush();
#else
#define dbg(...) 0
#define dbg2(x, j, n) 0
#endif
#define SZ(x) ((ll)((x).size()))
#define File(s, t) freopen(s ".txt", "r", stdin); freopen(t ".txt", "w", stdout);
#define input(j, n, a) for (int _i = (j); _i < (n)+(j); _i++) cin>> a[_i];
#define output(j, n, a, t) for (int _i = (j); _i < (n)+(j); _i++) cout<< a[_i] << (((t) && _i != (n)+(j)-1)? ' ' : '\n');
#define kill(x) return cout<< (x) << endl, 0
#define cl const ll
#define fr first
#define sc second
#define lc (v << 1)
#define rc (lc | 1)
#define mid ((l + r) >> 1)
#define All(x) (x).begin(), (x).end()

cl inf = sizeof(ll) == 4 ? (1e9 + 10) : (3e18), mod = 1e9 + 7, MOD = 998244353;

template <class A,class B> ostream& operator << (ostream& out,const pair<A,B>&a){return out<<'('<<a.first<<", "<<a.second<<')';}
template <class A> ostream& operator << (ostream& out, const vector<A> &a) {
	out<< '['; for (int i = -1; ++i < int(a.size());) out<< a[i] << (i + 1 < int(a.size()) ? ", " : ""); return out<<']'; }
template <class T, typename _t = less <T> > using Tree = tree <T, null_type, _t, rb_tree_tag, tree_order_statistics_node_update>;

cl N = 1e5 + 7;

priority_queue <pll, vector <pll>, greater <pll>> pq;
ll dis [40][N];
int n, m, k;
vector <pair <int, ll>> adj [N];
vector <int> imp;

void dijkstra (ll *dist) {
	for (int i = 1; i <= n; i++) pq.push({dist[i], i});
	for (int v; !pq.empty(); pq.pop()) {
		ll d = pq.top().fr; v = pq.top().sc;
		if (d != dist[v]) continue;
		for (auto &u : adj[v]) if (dist[u.fr] > dist[v] + u.sc) dist[u.fr] = dist[v] + u.sc, pq.push({dist[u.fr], u.fr});
	}
}

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

	memset(dis, 63, sizeof dis);

	cin>> n >> k >> m;
	imp.resize(k); for (auto &v : imp) cin>> v;
	for (int i = 0, v, u, w; i < m; i++) {
		cin>> v >> u >> w;
		adj[v].push_back({u, w});
		adj[u].push_back({v, w});
	}

	for (int msk = 1; msk < (1 << k); msk++) {
		if (__builtin_popcount(msk) == 1) dis[msk][imp[__builtin_ctz(msk)]] = 0;
		for (int i = 0; i < k; i++) if (msk >> i & 1) for (int j = 1; j <= n; j++)
			dis[msk][j] = min(dis[msk][j], dis[1 << i][j] + dis[msk ^ (1 << i)][j]);
		dijkstra(dis[msk]);
	}

	kill(dis[(1 << k) - 1][imp[0]]);

	cerr<< "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";

	return 0;
}
/*
4 3 6
1 3 4
1 2 4
1 3 9
1 4 6
2 3 2
2 4 5
3 4 8

*/

• Subtask 1: 22 / 22
• Subtask 2: 14 / 14
• Subtask 3: 15 / 15
• Subtask 4: 23 / 23
• Subtask 5: 26 / 26