Submission #698153

#	Time	Username	Problem	Language	Result	Execution time	Memory
698153		Tien_Noob	Designated Cities (JOI19_designated_cities)	C++17	23 / 100	137 ms	20352 KiB

designated_cities

//Make CSP great again
//Vengeance
#include <bits/stdc++.h>
#define TASK "TESTCODE"
using namespace std;
const int N = 2e5;
vector<pair<int, int> > adj[N + 1];
int n, q, w[2 * N];
long long sum_all;
void read()
{
    cin >> n;
    for (int i = 0; i < n - 1; ++ i)
    {
        int u, v, c, d;
        cin >> u >> v >> c >> d;
        adj[u].emplace_back(v, i * 2);
        adj[v].emplace_back(u, i * 2 + 1);
        w[2 * i] = c;
        w[2 * i + 1] = d;
        sum_all += c;
        sum_all += d;
    }
    cin >> q;
}
long long res[N + 1];
bool used[32];
bool DFS_brute(int u, int p)
{
    for (auto [v, i] : adj[u])
    {
        if (v == p)
        {
            continue;
        }
        used[i ^ 1] = true;
        DFS_brute(v, u);
    }
}
void sub1()
{
    memset(res, 0x3f, sizeof(res));
    for (int mask = 0; mask < (1 << n); ++ mask)
    {
        memset(used, 0, sizeof(used));
        for (int u = 1; u <= n; ++ u)
        {
            if ((mask >> (u - 1)) & 1)
            {
                DFS_brute(u, 0);
            }
        }
        long long sum = 0;
        for (int i = 0; i < 2 * n; ++ i)
        {
            if (!used[i])
            {
                sum += w[i];
            }
        }
        res[__builtin_popcount(mask)] = min(res[__builtin_popcount(mask)], sum);
    }
    while(q--)
    {
        int x;
        cin >> x;
        cout << res[x] << '\n';
    }
}
multiset<long long> f, trash;
long long dp_dw[N + 1], dp_up[N + 1], sum;
void DFS_dw(int u, int p)
{
    for (auto [v, i] : adj[u])
    {
        if (v == p)
        {
            continue;
        }
        DFS_dw(v, u);
        sum += w[i ^ 1];
        dp_dw[u] = max(dp_dw[u], dp_dw[v] + w[i]);
    }
    bool flag = true;
    for (auto [v, i] : adj[u])
    {
        if (v == p)
        {
            continue;
        }
        if (flag && dp_dw[u] == dp_dw[v] + w[i])
        {
            flag = false;
            continue;
        }
        f.insert(dp_dw[v] + w[i]);
    }
}
void DFS_up(int u, int p)
{
    long long g[2];
    int t[2];
    g[0] = g[1] = -1e18;
    t[0] = t[1] = -1;
    for (auto [v, i] : adj[u])
    {
        if (v == p)
        {
            continue;
        }
        dp_up[v] = dp_up[u] + w[i ^ 1];
        for (int j = 1; j >= 0; -- j)
        {
            if (dp_dw[v] + w[i] >= g[j])
            {
                for (int k = 0; k < j; ++ k)
                {
                    g[k] = g[k + 1];
                    t[k] = t[k + 1];
                }
                g[j] = dp_dw[v] + w[i];
                t[j] = v;
                break;
            }
        }
    }
    for (auto [v, i] : adj[u])
    {
        if (v == p)
        {
            continue;
        }
        for (int j = 1; j >= 0; -- j)
        {
            if (t[j] != v)
            {
                dp_up[v] = max(dp_up[v], g[j] + w[i ^ 1]);
                break;
            }
        }
        DFS_up(v, u);
    }
}
void DFS(int u, int p)
{
    res[1] = min(res[1], sum_all - sum);
    int cur = 1;
    long long t = 0;
    for (multiset<long long> :: reverse_iterator i = f.rbegin(); i != f.rend(); ++ i)
    {
        ++cur;
        t += *i;
        res[cur] = min(res[cur], sum_all - sum - t);
    }
    while(cur < n)
    {
        ++cur;
        res[cur] = min(res[cur], sum_all - sum - t);
    }
    for (auto [v, i] : adj[u])
    {
        if (v == p)
        {
            continue;
        }
        sum -= w[i ^ 1];
        sum += w[i];
        f.erase(f.find(dp_up[v] - w[i ^ 1]));
        f.erase(f.find(dp_dw[v] + w[i]));
        f.insert(dp_up[v]);
        f.insert(dp_dw[v]);
        DFS(v, u);
        sum += w[i ^ 1];
        sum -= w[i];
        f.insert(dp_up[v] - w[i ^ 1]);
        f.insert(dp_dw[v] + w[i]);
        f.erase(f.find(dp_up[v]));
        f.erase(f.find(dp_dw[v]));
    }
}
void sub4()
{
    memset(res, 0x3f, sizeof(res));
    DFS_dw(1, 0);
    f.insert(dp_dw[1]);
    f.insert(0);
    DFS_up(1, 0);
    DFS(1, 0);
    while(q--)
    {
        int x;
        cin >> x;
        cout << res[x] << '\n';
    }
}
void solve()
{
    if (n <= 16)
    {
        //sub1();
        //return ;
    }
    if (n <= 2000)
    {
        sub4();
        return ;
    }
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen(TASK".INP", "r"))
    {
        freopen(TASK".INP", "r", stdin);
        //freopen(TASK".OUT", "w", stdout);
    }
    int t = 1;
    bool typetest = false;
    if (typetest)
    {
        cin >> t;
    }
    for (int __ = 1; __ <= t; ++ __)
    {
        //cout << "Case " << __ << ": ";
        read();
        solve();
    }
}

Compilation message (stderr)

designated_cities.cpp: In function 'bool DFS_brute(int, int)':
designated_cities.cpp:39:1: warning: no return statement in function returning non-void [-Wreturn-type]
   39 | }
      | ^
designated_cities.cpp: In function 'int main()':
designated_cities.cpp:215:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  215 |         freopen(TASK".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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