Submission #105829

#	Time	Username	Problem	Language	Result	Execution time	Memory
105829		Alexa2001	Designated Cities (JOI19_designated_cities)	C++17	6 / 100	2029 ms	23776 KiB

designated_cities

#include <bits/stdc++.h>

using namespace std;

const int Nmax = 2e5 + 5;
typedef long long ll;


struct edge
{
    int to, toy, fromy;
};
vector<edge> v[Nmax];

bool used[Nmax];
int t[Nmax];
ll cost[Nmax], act_cost[Nmax], ans[Nmax];
int n;



ll dfs(int node, int dad = 0)
{
    t[node] = dad;

    ll ans = 0;
    for(auto it : v[node])
        if(it.to != dad)
        {
            cost[it.to] = cost[node] + it.toy;
            ans += it.fromy + dfs(it.to, node);
        }
    return ans;
}

void solve(int root)
{
    cost[root] = 0;
    ll curr = dfs(root);

    int i, j;
    for(i=1; i<=n; ++i) used[i] = 0, act_cost[i] = cost[i];

    ans[1] = max(ans[1], curr);

    for(i=2; i<=n; ++i)
    {
        int now = 1;
        for(j=1; j<=n; ++j)
            if(!used[j] && act_cost[j] > act_cost[now]) now = j;

        curr += act_cost[now];
        ans[i] = max(ans[i], curr);

        while(now)
        {
            used[now] = 1;
            now = t[now];
        }

        for(j=1; j<=n; ++j)
        {
            int x = j;
            while(!used[x]) x = t[x];
            act_cost[j] = cost[j] - cost[x];
        }
    }
}

int main()
{
  //  freopen("input", "r", stdin);
    cin.sync_with_stdio(false);

    ll sum = 0;
    int i;

    cin >> n;
    for(i=1; i<n; ++i)
    {
        int x, y, c1, c2;
        cin >> x >> y >> c1 >> c2;
        v[x].push_back({y, c1, c2});
        v[y].push_back({x, c2, c1});

        sum += c1 + c2;
    }

    for(i=1; i<=n; ++i) solve(i);

    int q;
    cin >> q;

    for(i=1; i<=q; ++i)
    {
        int x;
        cin >> x;
        cout << sum - ans[x] << '\n';
    }

    return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 0 / 7
• Subtask 3: 0 / 9
• Subtask 4: 0 / 17
• Subtask 5: 0 / 17
• Subtask 6: 0 / 44