Submission #1053975

#	Time	Username	Problem	Language	Result	Execution time	Memory
1053975		vjudge1	Evacuation plan (IZhO18_plan)	C++17	100 / 100	328 ms	57088 KiB

plan

#include <bits/stdc++.h>
#define ll long long
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fi first
#define se second
#define f(i, a, b) for (int i = a; i <= b; i++)
using namespace std;

/*
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                    // == [[ << - >> ]] == //
                    //  Author: Jeb Coder  //
                    //    Language: C++    //
*/

const int NMax = 1e5 + 5;
ll n, m, x, y, w, k, q;
ll a[NMax], p[NMax], parent[NMax], s[NMax], id[NMax], dist[NMax];
vector<pll> adj[NMax];
bool mark[NMax];
set<ll>sz[NMax];

bool COMP (ll a, ll b)
{
    return dist[a] > dist[b];
}

void Dijsktra() 
{
    for (int i = 1; i <= n; i++)
        dist[i] = LLONG_MAX;

    priority_queue<pll,vector<pll>, greater<pll> >q;
    for (int i = 1; i <= k; i++) {
        dist[a[i]] = 0;
        q.push ({0, a[i]});
    }

    while (!q.empty()) {
        ll u = q.top().se; q.pop();
        if(mark[u]) continue;

        mark[u] = true;
        for (auto v : adj[u]) {
            ll it = v.fi;
            ll w = v.se;
            if (dist[it] > dist[u] + w) {
                dist[it] = dist[u] + w;
                q.push ({dist[it], it});
            }
        }
    }
}

ll Find_Set(ll u)
{
    if (u == parent[u]) return u;
    return parent[u] = Find_Set (parent[u]);
}

void Union_Set (ll u, ll v)
{
    u = Find_Set(u); v = Find_Set(v);

    if (u == v) return;
    if (s[u] < s[v]) swap(u, v);
    parent[v] = u;
    s[u] += s[v];

    for (auto it : sz[v]) {
        if (sz[u].find (it) != sz[u].end()) {
            sz[u].erase (it);
            p[it] = w;
        }
        else sz[u].insert (it);
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
//     freopen(".INP", "r", stdin);
//     freopen(".OUT", "w", stdout);

    cin >> n >> m;
    while (m--) {
        cin >> x >> y >> w;
        adj[x].push_back ({y, w});
        adj[y].push_back ({x, w});
    }

    cin >> k;
    for (int i = 1; i <= k; i++) cin >> a[i];

    Dijsktra();

    cin >> q;
    for (int i = 1; i <= q; i++) {
        cin >> x >> y;
        sz[x].insert (i);
        sz[y].insert (i);
    }

    for (int i = 1; i <= n; i++) {
        id[i] =  i;
        parent[i] = i;
        s[i] = i;
    }

    sort (id + 1, id + n + 1, COMP);
    memset(mark,0,sizeof(mark));
    for (int i = 1; i <= n; i++) {
        x = id[i];
        mark[x] = true;
        w = dist[x];
        for (auto it : adj[x]) {
            y = it.fi;
            if (mark[y]) Union_Set (x,y);
        }
    }

    for (int i = 1; i <= q; i++) 
        cout << p[i] << '\n';

    return 0;
}

/*

*/

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