Submission #1329245

#	Time	Username	Problem	Language	Result	Execution time	Memory
1329245		chikien2009	Designated Cities (JOI19_designated_cities)	C++20	7 / 100	264 ms	19584 KiB

designated_cities

#include <bits/stdc++.h>

using namespace std;

void setup()
{
#ifndef ONLINE_JUDGE
    freopen("test.inp", "r", stdin);
    freopen("test.out", "w", stdout);
#endif
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
}

int n, q, a, b, c, d;
long long all;
long long f[200000], res[200001];
vector<array<int, 3>> g[200000];

inline void DFS(int node, int par)
{
    for (auto & i : g[node])
    {
        if (i[0] != par)
        {
            DFS(i[0], node);
            f[node] += f[i[0]] + i[2];
        }
    }
}

inline void DFS1(int node, int par, long long pre)
{
    res[1] = max(res[1], f[node] + pre);
    for (auto & i : g[node])
    {
        if (i[0] != par)
        {
            DFS1(i[0], node, pre + f[node] - f[i[0]] - i[2] + i[1]);
        }
    }
}

int main()
{
    // setup();

    cin >> n;
    for (int i = 0; i < n - 1; ++i)
    {
        cin >> a >> b >> c >> d;
        g[a - 1].push_back({b - 1, c, d});
        g[b - 1].push_back({a - 1, d, c});
        all += c + d;
    }
    DFS(0, 0);
    DFS1(0, 0, 0);
    cout << all - res[1] << "\n";
    return 0;
}

Compilation message (stderr)

designated_cities.cpp: In function 'void setup()':
designated_cities.cpp:8:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 |     freopen("test.inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
designated_cities.cpp:9:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |     freopen("test.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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