Submission #571528

#	Time	Username	Problem	Language	Result	Execution time	Memory
571528		vbee	Evacuation plan (IZhO18_plan)	C++14	12 / 100	394 ms	36924 KiB

plan

#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define ii pair<int,int>
#define vii vector<ii>
#define vi vector<int>
#define fi first
#define se second
#define TASK "evacuationplan"
#define ll long long
#define pll pair<ll, ll>
#define vll vector<ll>
#define vpll vector<pll>
#define pb push_back
#define MASK(i) (1 << (i))
#define BIT(x, i) ((x >> (i)) & 1)
 
using namespace std;

const int oo = 1e9 + 7;
const ll loo = (ll)1e18 + 7; 
const int N = 1e5 + 7;
const int M = 1e3 + 7;
const int LOG = 15;

int n, m, k, q, adist[M][M], f[MASK(LOG)][16], minidist[N], ans[16][16];
vector<pair<int, int> > g[N];
vector<int> npp;

void minimize(int &a, int b){
	if (a > b) a = b;
}

void apsp(int i){
	minidist[i] = oo;
	for (int j = 1; j <= n; j++) adist[i][j] = oo;
	adist[i][i] = 0;
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> kew;
	kew.push({0, i});
	while (!kew.empty()){
		auto k = kew.top();
		kew.pop();
		if (k.fi > adist[i][k.se]){
			continue;
		}
		for (auto u : g[k.se]) {
			if (k.fi + u.se < adist[i][u.fi]){
				adist[i][u.fi] = k.fi + u.se;
				kew.push({k.fi + u.se, u.fi});
			}
		}
	}
	for (auto u : npp) minidist[i] = min(minidist[i], adist[i][u]);
	return;
}

vector<pair<int, int> > queries;

// bool check(int s, int t, int x){
// 	queue<int> kew;
// }
int main() {
	ios_base::sync_with_stdio(0); cin.tie(0);
	// freopen(TASK".inp", "r", stdin);
	// freopen(TASK".out", "w", stdout);
	cin >> n >> m;
	map<pair<int, int>, bool> checkexist;
	for (int i = 1; i <= m; i++){
		int u, v, w; cin >> u >> v >> w;
		g[u].pb({v, w});
		g[v].pb({u, w});
		checkexist[{u, v}] = checkexist[{v, u}] = true;
	}
	cin >> k;
	for (int i = 1; i <= k; i++) {
		int x; cin >> x;
		npp.pb(x);
	}
	bool sub12 = true;
	cin >> q;
	while (q--){
		int x, y; cin >> x >> y;
		queries.pb({x, y});
		if (!checkexist[{x, y}]) sub12 = false;
	}
	if (n <= 1000 && m <= 1000 && q <= 1000 && sub12){
		for (int i = 1; i <= n; i++) apsp(i);
		for (int j = 0; j < queries.size(); j++) {
			int x = queries[j].fi, y = queries[j].se;
			int res = oo;
			for (int i = 0; i < (int)npp.size(); i++){
				res = min({res, adist[x][npp[i]], adist[y][npp[i]]});
			}
			cout << res << "\n";
		}
	}
	if (n <= 15 && m <= 200 && q <= 200){
		for (int i = 1; i <= n; i++) apsp(i);
		for (int sta = 0; sta < n; sta++){
			for (int mask = 0; mask < MASK(n); mask++) for (int j = 0; j < n; j++) f[mask][j] = oo;
			f[MASK(sta)][sta] = minidist[sta + 1];
			for (int mask = 0; mask < MASK(n); mask++){
				for (int i = 0; i < n; i++) if (f[mask][i] != oo){
					int id = i + 1;
					for (auto u : g[id]){
						int cur = u.fi - 1;
						if (!BIT(mask, cur)){
							minimize(f[mask | MASK(cur)][cur], min(f[mask][i], minidist[u.fi])); 
						}
					}
				}
			}
			for (int mask = 0; mask < MASK(n); mask++){
				for (int i = 0; i < n; i++) if (f[mask][i] != oo){
					ans[sta + 1][i + 1] = max(ans[sta + 1][i + 1], f[mask][i]);
				}
			}
		}
		for (auto u : queries){
			cout << ans[u.fi][u.se] << "\n";
		}
	}
	return 0;
}

Compilation message (stderr)

plan.cpp: In function 'int main()':
plan.cpp:88:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |   for (int j = 0; j < queries.size(); j++) {
      |                   ~~^~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 13
• Subtask 3: 12 / 12
• Subtask 4: 0 / 19
• Subtask 5: 0 / 46