Submission #1084221

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084221		anhthi	Sjekira (COCI20_sjekira)	C++14	110 / 110	55 ms	25708 KiB

sjekira

#include <bits/stdc++.h>
 
using namespace std;
 
#define fi first
#define se second
#define ll long long
#define pll pair<ll, ll>
#define pii pair<int, int>
#define mp(x, y) make_pair(x, y)
#define sz(v) ((int) (v).size())
#define all(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define BIT(x, y) (((x) >> (y)) & 1)
#define clz __builtin_clzll
#define ctz __builtin_ctzll
#define popcount __builtin_popcount
#define lg(x) (63 - clz(x))
 
template <class X, class Y>
    inline bool maximize(X &x, Y y) {
        if (x < y) return x = y, true;
        return false;
    }
template <class X, class Y>
    inline bool minimize(X &x, Y y) {
        if (x > y) return x = y, true;
        return false;
    }
template <class X>
    inline void compress(vector<X> &a) {
        sort(all(a)); a.resize(unique(all(a)) - a.begin());
    }
 
const ll oo = (ll) 1e17;
const int inf = (int) 1e9, mod = (int) 1e9 + 7;
const int mxn = (int) 1e5 + 5, mxm = (int) 11;
int n;
int t[mxn];
 
vector<int> node;
 
ll ans;
bool ok[mxn];
vector<int> g[mxn];
 
class Dsu {
    int n;
    vector<int> par, sz;
 
    vector<int> max_cc;
//    set<pair<int, int>> s;
 
public:
    Dsu(int n) : n(n) {
        par.resize(n+1);
        sz.resize(n+1, 1);
        max_cc.resize(n+1);
        for (int i = 1; i <= n; ++i) {
            par[i] = i;
            max_cc[i] = t[i];
        }
    }
    int find_set(int u) {
        return (u == par[u] ? u : par[u] = find_set(par[u]));
    }
 
    bool union_set(int u, int v) {
        u = find_set(u);
        v = find_set(v);
        if (u == v) return false;
        if (sz[u] < sz[v]) swap(u, v);
        par[v] = u; sz[u] += sz[v];
        maximize(max_cc[u], max_cc[v]);
        return true;
    }
 
    int get_max(int u) { return max_cc[find_set(u)]; }
 
};
 
ll dnc(int p, Dsu &dsu) {
    if (p == sz(node)) return 0;
    ll res = dnc(p+1, dsu);
    for (int v : g[node[p]]) if (ok[v]) {
        res += t[node[p]] + dsu.get_max(v);
        dsu.union_set(node[p], v);
    }
    ok[node[p]] = true;
    return res;
}
 
int main() {
 
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
 
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> t[i];
    }
    for (int i = 1; i < n; ++i) {
        int u, v;
        cin >> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    node.resize(n);
    iota(all(node), 1);
    sort(all(node), [&](int &u, int &v) {
        return t[u] > t[v];
    });
 
    Dsu dsu(n);
    cout << dnc(0, dsu);
 
    return 0;
}

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