Submission #978041

#	Time	Username	Problem	Language	Result	Execution time	Memory
978041		steveonalex	Toll (APIO13_toll)	C++17	56 / 100	225 ms	15440 KiB

toll

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;

#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)

// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}

ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}

ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}

template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b){a = b; return true;}
        return false;
    }
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b){a = b; return true;}
        return false;
    }
template <class T>
    void printArr(T a, string separator = " ", string finish = "\n", ostream& out = cout){
        for(auto i: a) out << i << separator;
        out << finish;
    }
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

struct DSU{
    int n;
    vector<int> parent, sz;

    DSU(int _n){
        n = _n;
        parent.resize(n+1); sz.resize(n+1, 1);
        for(int i = 1; i<=n; ++i) parent[i] = i;
    }

    int find_set(int u){return (u == parent[u]) ? u : (parent[u] = find_set(parent[u]));}
    bool same_set(int u, int v){return find_set(u) == find_set(v);}
    bool join_set(int u, int v){
        u = find_set(u), v = find_set(v);
        if (u != v){
            if (sz[u] < sz[v]) swap(u, v);
            parent[v] = u;
            sz[u] += sz[v];
            return true;
        }
        return false;
    }
};

const int N = 1e3 + 69, LOG_N = 10;

int n, m, k;
vector<array<int, 3>> path, useful;
vector<pair<int, int>> money;
vector<pair<int, int>> graph[N];
// int parent[LOG_N][N];
// int max_path[LOG_N][N];
// int h[N];
int goon[N];

// void dfs(int u, int p){
//     h[u] = h[p] + 1;
//     for(int j = 1; MASK(j) < h[u]; ++j){
//         int prev = parent[j-1][u];
//         parent[j][u] = parent[j-1][prev];
//         max_path[j][u] = max(max_path[j-1][u], max_path[j-1][prev]);
//     }

//     for(pair<int, int> v: graph[u]) if (v.first != p){
//         parent[0][v.first] = u;
//         max_path[0][v.first] = v.second;
//         dfs(v.first, u);
//     }
// }

// int LCA(int u, int v){
//     if (h[u] < h[v]) swap(u, v);
//     int diff = h[u] - h[v];
//     for(int j = 0; j < LOG_N; ++j) if (GETBIT(diff, j))
//         u = parent[j][u];
//     if (u == v) return u;
//     for(int j = LOG_N - 1; j>=0; --j) if (parent[j][u] != parent[j][v]){
//         u = parent[j][u];
//         v = parent[j][u];
//     }
//     return parent[0][u];
// }

// int get_max_path(int u, int v){
//     int lck = LCA(u, v);
//     int diff = h[u] - h[lck];
//     int ans = 0;
//     for(int j = 0; j< LOG_N; ++j) if (GETBIT(diff, j)) {
//         maximize(ans, max_path[j][u]);
//         u = parent[j][u];
//     }
//     diff = h[v] - h[lck];
//     for(int j = 0; j<LOG_N; ++j) if (GETBIT(diff, j)){
//         maximize(ans, max_path[j][v]);
//         v = parent[j][v];
//     }
//     return ans;
// }

namespace Nig{
    vector<pair<int, int>> graph[N];
    ll chode[N];
    vector<array<int, 3>> ans;
    void reset(){
        for(int i = 1; i<=n; ++i){
            graph[i].clear();
        }
    }

    void dfs(int u, int p){
        chode[u] = goon[u];
        for(pair<int, int> v: graph[u]) if (v.first != p){
            dfs(v.first, u);
            chode[u] += chode[v.first];
            if (v.second) ans.push_back({u, v.first, chode[v.first]});
        }
    }

    vector<array<int, 3>> go(DSU &mst){
        ans.clear();
        for(array<int, 3> i: useful){
            int u = i[0], v = i[1];
            if (mst.join_set(u, v)){
                graph[u].push_back({v, 0});
                graph[v].push_back({u, 0});
            }
        }
        dfs(1, 1);
        return ans;
    }
}

int main(void){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    cin >> n >> m >> k;
    path.resize(m);
    for(int i = 0; i<m; ++i){
        for(int j = 0;j < 3; ++j) cin >> path[i][j];
    }
    sort(ALL(path), [] (array<int, 3> x, array<int, 3> y){return x[2] < y[2];});

    DSU mst(n);
    for(int i = 0; i<m; ++i){
        int u = path[i][0], v = path[i][1], w = path[i][2];
        if (mst.join_set(u, v)){
            useful.push_back(path[i]);
            graph[u].push_back({v, w});
            graph[v].push_back({u, w});
        }
    }
    money.resize(k);
    for(int i = 0; i<k; ++i) cin >> money[i].first >> money[i].second;

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

    ll ans = 0;
    for(int mask = 1; mask < MASK(k); ++mask){
        DSU mst(n);
        bool check = true;
        for(int i = 0; i<k; ++i) if (GETBIT(mask, i)){
            check = check && mst.join_set(money[i].first, money[i].second);
        }
        if (check == false) continue;

        Nig::reset();

        // cerr << string(50, '-') << endl;

        for(int i= 0; i<k; ++i) if (GETBIT(mask, i)) {
            int u = money[i].first, v = money[i].second;
            Nig::graph[u].push_back({v, 1});
            Nig::graph[v].push_back({u, 1});
        }

        vector<array<int, 3>> edging = Nig::go(mst);
        sort(ALL(edging), [](array<int, 3> x, array<int, 3> y){return x[2] > y[2];});

        vector<int> toll(edging.size(), -1);
        for(int i = 0; i < edging.size(); ++i){
            vector<array<int, 3>> sex = useful;
            for(int j = 0; j<i; ++j){
                int u = edging[j][0], v = edging[j][1], w = toll[j];
                sex.push_back({{-u, -v, w}});
            }
            sort(ALL(sex), [](array<int, 3> x, array<int, 3> y){
                if (x[2] != y[2]) return x[2] < y[2];
                return x[1] < y[1];
            });

            DSU mst(n);
            for(int j = i+1; j<edging.size(); ++j){
                int u = edging[j][0], v = edging[j][1];
                mst.join_set(u, v);
            }
            int u = edging[i][0], v = edging[i][1];
            for(array<int, 3> item: sex){
                if (mst.join_set(abs(item[0]), abs(item[1]))){
                    if (mst.same_set(u, v) && toll[i] == -1){
                        toll[i] = item[2];
                    }
                }
            }
        }

        ll cur = 0;
        for(int i = 0; i<edging.size(); ++i) cur += 1LL * toll[i] * edging[i][2];
        // for(int i = 0; i<edging.size(); ++i) cerr << toll[i] << " " << edging[i][2] << "\n";

        // cerr << cur << endl;
        maximize(ans, cur);
    }
    cout << ans << "\n";

    return 0;
}

Compilation message (stderr)

toll.cpp: In function 'void Nig::dfs(int, int)':
toll.cpp:140:67: warning: narrowing conversion of 'Nig::chode[v.std::pair<int, int>::first]' from 'll' {aka 'long long int'} to 'int' [-Wnarrowing]
  140 |             if (v.second) ans.push_back({u, v.first, chode[v.first]});
      |                                                      ~~~~~~~~~~~~~^
toll.cpp: In function 'int main()':
toll.cpp:205:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  205 |         for(int i = 0; i < edging.size(); ++i){
      |                        ~~^~~~~~~~~~~~~~~
toll.cpp:217:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  217 |             for(int j = i+1; j<edging.size(); ++j){
      |                              ~^~~~~~~~~~~~~~
toll.cpp:232:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  232 |         for(int i = 0; i<edging.size(); ++i) cur += 1LL * toll[i] * edging[i][2];
      |                        ~^~~~~~~~~~~~~~

• Subtask 1: 16 / 16
• Subtask 2: 18 / 18
• Subtask 3: 22 / 22
• Subtask 4: 0 / 22
• Subtask 5: 0 / 22