Submission #630173

#	Time	Username	Problem	Language	Result	Execution time	Memory
630173		Hacv16	Sjekira (COCI20_sjekira)	C++17	110 / 110	80 ms	58940 KiB

sjekira

#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int MAX = 2e6 + 15;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;

#define pb push_back
#define sz(x) (int) x.size()
#define fr first
#define sc second
#define mp make_pair
#define all(x) x.begin(), x.end()
#define dbg(x) cerr << #x << ": " << "[ " << x << " ]\n"

ll n, t[MAX], pai[MAX], mark[MAX], mx[MAX], sze[MAX], ans;
vector<ll> adj[MAX];

ll find(ll u){
    if(pai[u] == u) return u;
    return pai[u] = find(pai[u]);
}

ll join(ll u, ll v){
    u = find(u), v = find(v);
    if(u == v) return 0;

    if(sze[v] > sze[u]) swap(u, v);

    ll cut = mx[u] + mx[v];
    pai[v] = u, sze[u] += sze[v], mx[u] = max(mx[u], mx[v]);
    return cut;
}

ll getMax(ll u){
    return mx[find(u)];
}

bool cmp(ll u, ll v){
    return t[u] > t[v];
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); 

    cin >> n;

    for(int i = 1; i <= n; i++)
        cin >> t[i];

    for(int i = 1; i < n; i++){
        ll u, v; cin >> u >> v; 
        adj[u].pb(v); adj[v].pb(u);
    }

    for(int i = 1; i <= n; i++)
        pai[i] = i, mx[i] = t[i], sze[i] = 1;

    vector<ll> order(n);
    iota(all(order), 1);
    sort(all(order), cmp);

    vector<pii> edges;

    for(auto u : order){
        for(auto v : adj[u]){
            if(mark[v]) continue;
            edges.pb({u, v});
        }

        mark[u] = true;
    }

    reverse(all(edges));

    for(auto e : edges)
        ans += join(e.fr, e.sc);

    cout << ans << '\n';

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 60 / 60