Submission #1040650

#	Time	Username	Problem	Language	Result	Execution time	Memory
1040650		vjudge1	Evacuation plan (IZhO18_plan)	C++17	41 / 100	548 ms	44328 KiB

plan

#include<bits/stdc++.h>
#define INF 1e18
#define fi first
#define se second
#define FOR(i, k, n) for(ll i = k; i <= n; i++)
#define FOR1(i, k, n) for(ll i = k; i >= n; i--)
#define pb push_back
#define fastio ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define vi vector<int>
#define pii pair<int, int>
#define vii vector<pii>
#define ll long long
#define vll vector<ll>
#define pll pair<ll, ll>
#define re return 0
#define mii map<int, int>
#define input "BAI1.inp"
#define output "BAI1.out"
#define rf 	freopen(input, "r", stdin); freopen(output, "w", stdout)
using namespace std;
const int maxn = 1e5 + 5;
const int mod = 1e9 + 7;
ll dp[maxn];
int n, m, par[maxn], sz[maxn], L[maxn], R[maxn], mid[maxn], kq[maxn];
bool vis[maxn];
vii adj[maxn];
vi event[maxn];
pii a[maxn];
void make_set()
{
	FOR(i, 1, n)
	{
		sz[i] = 1;
		par[i] = i;
	}
}
int find(int u)
{
	if(u == par[u])
		return u;
	return par[u] = find(par[u]);
}
void Union(int u, int v)
{
	u = find(u);
	v = find(v);
	if(sz[u] > sz[v])
		swap(u, v);
	par[u] = v;
	sz[v] += sz[u];
}
int main()
{
	fastio;
	cin >> n >> m;
	FOR(i, 1, m)
	{
		int u, v, w;
		cin >> u >> v >> w;
		adj[u].pb({v, w});
		adj[v].pb({u, w});
	}
	priority_queue<pll, vector<pll>, greater<pll>> Q;
	FOR(i, 1, n)
		dp[i] = INF;
	int k;
	cin >> k;
	FOR(i, 1, k)
	{
		int u;
		cin >> u;
		dp[u] = 0;
		Q.push({0, u});
	}
	while(!Q.empty())
	{
		int u = Q.top().se;
		Q.pop();
		if(vis[u])
			continue;
		vis[u] = 1;
		for(auto x : adj[u])
		{
			int v = x.fi;
			int w = x.se;
			if(dp[v] > dp[u] + w)
			{
				dp[v] = dp[u] + w;
				Q.push({dp[v], v});
			}
		}
	}
	int q;
	cin >> q;
	FOR(i, 1, q)
		cin >> a[i].fi >> a[i].se;
	vii vv;
	FOR(i, 1, n)
		vv.pb({dp[i], i});
	sort(vv.begin(), vv.end());
	FOR(i, 1, q)
	{
		L[i] = 0;
		R[i] = n - 1;
	}
	while(1)
	{
		make_set();
		bool kt = 0;
		FOR(i, 1, n)
			event[i].clear();
		FOR(i, 1, q)
		{
			if(L[i] > R[i])
				continue;
			kt = 1;
			mid[i] = (L[i] + R[i]) / 2;
			event[mid[i]].pb(i);
		}
		if(kt == 0)
			break;
		FOR1(i, vv.size() - 1, 0)
		{
			int u = vv[i].se;
			for(auto x : adj[u])
			{
				int v = x.fi;
				if(dp[v] < dp[u])
					continue;
				if(find(u) != find(v))
					Union(u, v);
			}
			for(auto id : event[i])
			{
				if(find(a[id].fi) == find(a[id].se))
				{
					kq[id] = i;
					L[id] = mid[id] + 1;
				}
				else
					R[id] = mid[id] - 1;
			}
		}
	}
	FOR(i, 1, q)
	{
		cout << vv[kq[i]].fi << "\n";
	}
	re;
}

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