Submission #561989

#	Time	Username	Problem	Language	Result	Execution time	Memory
561989		hoanghq2004	Toll (APIO13_toll)	C++14	100 / 100	1797 ms	14232 KiB

toll

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;

const int N = 1e5 + 10;

int n, m, k;
int comp[N];
int par[N], sz[N], root[N];
vector <pair <int, int> > g[N];
int d[N], cap[N];
long long tot[N], a[N];

int Find(int u) {
    return (u == root[u] ? u : root[u] = Find(root[u]));
}

int Union(int u, int v) {
    if ((u = Find(u)) == (v = Find(v))) return 0;
    if (sz[u] < sz[v]) swap(u, v);
    root[v] = u;
    sz[u] += sz[v];
    return 1;
}

void dfs(int u, int p) {
    assert(comp[u] == 0);
    comp[u] = m;
    for (auto [v, w]: g[u]) {
        if (v == p) continue;
        dfs(v, u);
    }
}

void get(int u, int p) {
    tot[u] = a[u];
    for (auto [v, w]: g[u]) {
        if (v == p) continue;
        d[v] = d[u] + 1;
        par[v] = u;
        get(v, u);
        tot[u] += tot[v];
    }
}

int main() {
//    freopen("toll.inp", "r", stdin);
//    freopen("toll.ans", "w", stdout);
    ios :: sync_with_stdio(0); cin.tie(0);
    cin >> n >> m >> k;
    vector <tuple <int, int, int> > e, ne;
    while (m--) {
        int u, v, w;
        cin >> u >> v >> w;
        e.push_back({w, u, v});
    }
    sort(e.begin(), e.end());
    vector <pair <int, int> > add;
    for (int i = 1; i <= n; ++i) root[i] = i, sz[i] = 1;
    while (k--) {
        int u, v;
        cin >> u >> v;
        Union(u, v);
        add.push_back({u, v});
    }
    for (auto [w, u, v]: e) {
        if (Union(u, v)) g[u].push_back({v, 0}), g[v].push_back({u, 0});
    }
    m = 0;
    for (int i = 1; i <= n; ++i) {
        if (!comp[i]) {
            ++m;
            dfs(i, 0);
        }
    }
//    assert(m <= 20);
    for (int i = 1; i <= n; ++i) {
        int x;
        cin >> x;
        a[comp[i]] += x;
    }
    n = m;
    for (int i = 1; i <= n; ++i) root[i] = i, sz[i] = 1;
    for (auto &[u, v]: add) u = comp[u], v = comp[v];
    for (auto &[w, u, v]: e) {
        u = comp[u], v = comp[v];
        if (Union(u, v)) ne.push_back({w, u, v});
    }
    for (int i = 1; i <= n; ++i) g[i].clear();
    swap(e, ne);
//    cout << m << '\n';
    long long ans = 0;
    for (int mask = 0; mask < (1 << add.size()); ++mask) {
        for (int i = 1; i <= n; ++i) root[i] = i, sz[i] = 1, g[i].clear();
        int ok = 1;
        for (int i = 0; i < add.size(); ++i) {
            if (mask >> i & 1) {
                if (Union(add[i].first, add[i].second)) {
                    g[add[i].first].push_back({add[i].second, 1});
                    g[add[i].second].push_back({add[i].first, 1});
                } else {
                    ok = 0;
                    break;
                }
            }
        }
        if (ok == 0) continue;
        vector <tuple <int, int, int> > rem;
        for (auto [w, u, v]: e) {
            if (Union(u, v)) {
                g[u].push_back({v, 0});
                g[v].push_back({u, 0});
            } else rem.push_back({w, u, v});
        }
        get(comp[1], 0);
        for (int i = 1; i <= n; ++i) cap[i] = 1e9;
        for (auto [w, u, v]: rem) {
            while (u != v) {
                if (d[u] < d[v]) swap(u, v);
                cap[u] = min(cap[u], w);
                u = par[u];
            }
        }
        long long cur = 0;
        for (int u = 1; u <= n; ++u)
            for (auto [v, type]: g[u]) {
                if (type && par[u] == v) assert(cap[u] < 1e9), cur += tot[u] * cap[u];
            }
        ans = max(ans, cur);
    }
//    cerr << ans;
    cout << ans;
}

Compilation message (stderr)

toll.cpp: In function 'void dfs(int, int)':
toll.cpp:37:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   37 |     for (auto [v, w]: g[u]) {
      |               ^
toll.cpp: In function 'void get(int, int)':
toll.cpp:45:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   45 |     for (auto [v, w]: g[u]) {
      |               ^
toll.cpp: In function 'int main()':
toll.cpp:74:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   74 |     for (auto [w, u, v]: e) {
      |               ^
toll.cpp:92:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   92 |     for (auto &[u, v]: add) u = comp[u], v = comp[v];
      |                ^
toll.cpp:93:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   93 |     for (auto &[w, u, v]: e) {
      |                ^
toll.cpp:104:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  104 |         for (int i = 0; i < add.size(); ++i) {
      |                         ~~^~~~~~~~~~~~
toll.cpp:117:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  117 |         for (auto [w, u, v]: e) {
      |                   ^
toll.cpp:125:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  125 |         for (auto [w, u, v]: rem) {
      |                   ^
toll.cpp:134:23: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  134 |             for (auto [v, type]: g[u]) {
      |                       ^

• Subtask 1: 16 / 16
• Subtask 2: 18 / 18
• Subtask 3: 22 / 22
• Subtask 4: 22 / 22
• Subtask 5: 22 / 22