Submission #970809

#	Time	Username	Problem	Language	Result	Execution time	Memory
970809		thinknoexit	Security Guard (JOI23_guard)	C++17	100 / 100	175 ms	30972 KiB

guard

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 200200;
int a[N], p[N];
struct Edge {
    int u, v;
    ll w;
    bool operator < (const Edge& o) const {
        return w > o.w;
    }
};
vector<Edge> e;
priority_queue<Edge> pq;
int fr(int i) {
    return p[i] == i ? i : p[i] = fr(p[i]);
}
ll res[N], cost[N];
int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int n, m, q;
    cin >> n >> m >> q;
    for (int i = 1;i <= n;i++) cin >> a[i];
    int mn = *min_element(a + 1, a + 1 + n);
    int mx = *max_element(a + 1, a + 1 + n);
    res[n - 1] = mx + 1ll * (n - 2) * mn;
    for (int i = 1;i <= n;i++) p[i] = i;
    while (m--) {
        int u, v;
        cin >> u >> v;
        e.push_back({ u, v, a[u] + a[v] });
    }
    int idx = 0;
    sort(e.rbegin(), e.rend());
    for (auto& x : e) {
        int u = x.u, v = x.v;
        int pu = fr(u), pv = fr(v);
        if (pu == pv) continue;
        p[pu] = pv;
        if (a[u] < a[v]) swap(u, v);
        pq.push({ u, v, a[v] - mn });
    }
    for (int i = 1;i <= n;i++) p[i] = i, cost[i] = a[i] + mn;
    int now = n - 2;
    while (now >= 0) {
        auto x = pq.top();
        pq.pop();
        int u = x.u, v = x.v;
        if (fr(u) == fr(v)) continue;
        ll w = x.w;
        ll w2 = a[u] + a[v] - max(cost[fr(u)], cost[fr(v)]);
        if (w != w2) {
            pq.push({ u, v, w2 });
            continue;
        }
        if (cost[fr(u)] < cost[fr(v)]) swap(u, v);
        p[fr(u)] = fr(v);
        res[now] = res[now + 1] + w;
        now--;
    }
    for (int i = 0;i <= q;i++) {
        cout << res[min(i, n - 1)] << '\n';
    }
    return 0;
}
/*
2 3
1 2
3 6
8 9
6 9
9 10
1 4
7 8
2 5
*/

Compilation message (stderr)

guard.cpp: In function 'int main()':
guard.cpp:33:9: warning: unused variable 'idx' [-Wunused-variable]
   33 |     int idx = 0;
      |         ^~~

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 13 / 13
• Subtask 5: 8 / 8
• Subtask 6: 18 / 18
• Subtask 7: 24 / 24