Submission #1245859

#	Time	Username	Problem	Language	Result	Execution time	Memory
1245859		tuanhung0	Cities (BOI16_cities)	C++20	Compilation error	0 ms	0 KiB

cities

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define fi first
#define se second
#define pb push_back
#define FOR(i, l, r) for (int i = l; i <= r; ++i)
#define FORD(i, l, r) for (int i = r; i >= l; --i)
#define BIT(x, i) ((x) >> (i)) & 1
#define task ""
const int nmax = 1e5;
const ll mod = 1e9 + 7;
const int inf = 0x3f3f3f3f;
const ll linf = 1e15;
int n, m, k;
vector<pair<int, int>> adj[nmax + 5];
int dist[nmax + 5][35];

void solve() {
	FOR(mask, 1, (1 << k) - 1) {
		priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
		FOR(i, 1, n) {
			for (int _mask = mask; _mask; _mask = (_mask - 1) & mask) {
				dist[i][mask] = min(dist[i][mask], dist[i][_mask] + dist[i][mask ^ _mask]);
			}
			if (dist[i][mask] < inf) pq.push({dist[i][mask], i});
		}
		// cout << mask << " : ";
		while (!pq.empty()) {
			pair<int, int> tp = pq.top();
			pq.pop();
			int d = tp.fi, u = tp.se;
			if (d > dist[u][mask]) continue;
			// cout << u << ' ';
			for (pair<int, int> v : adj[u]) {
				if (dist[v.fi][mask] > dist[u][mask] + v.se) {
					dist[v.fi][mask] = dist[u][mask] + v.se;
					pq.push({dist[v.fi][mask], v.fi});
				}
			}
		}
		// cout << '\n';
	}
	int ans = inf;
	FOR(i, 1, n) ans = min(ans, dist[i][(1 << k) - 1]);
	cout << ans;
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	if (fopen(task".inp", "r")) {
		freopen(task".inp", "r", stdin);
		freopen(task".out", "w", stdout);
	}
	cin >> n >> k >> m;
	memset(dist, 0x3f3f3f3f, sizeof dist);
	FOR(i, 0, k - 1) {
		int x; cin >> x;
		dist[x][(1 << i)] = 0;
	}
	FOR(i, 1, m) {
		int u, v, w;
		cin >> u >> v >> w;
		adj[u].pb({v, w});
		adj[v].pb({u, w});
	}
	solve();
	return 0;
}

Compilation message (stderr)

cc1plus: error: '::main' must return 'int'
cities.cpp: In function 'int main()':
cities.cpp:54:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |                 freopen(task".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
cities.cpp:55:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |                 freopen(task".out", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~