Submission #503713

#	Time	Username	Problem	Language	Result	Execution time	Memory
503713		Stickfish	Paths (RMI21_paths)	C++17	36 / 100	1088 ms	12144 KiB

Main

#include <iostream>
#include <vector>
using namespace std;
using ll = long long;

const int MAXN = 100008;
vector<pair<int, ll>> edg[MAXN];
vector<ll> prof[MAXN];

vector<ll> merge(vector<ll>& a, vector<ll>& b) {
    int n = a.size();
    int m = b.size();
    vector<ll> ans(n + m - 1);
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            ans[i + j] = max(ans[i + j], a[i] + b[j]);
        }
    }
    return ans;
}

vector<ll> dfs(int v, int rt) {
    if (edg[v].empty() || edg[v].size() == 1 && edg[v][0].first == rt) {
        return {0, 0};
    }
    vector<vector<ll>> prof_edg;
    for (auto [u, d] : edg[v]) {
        if (u == rt)
            continue;
        prof_edg.push_back(dfs(u, v));
        for (auto& x : prof_edg.back()) {
            x += d;
        }
        prof_edg.back()[0] -= d;
    }
    while (prof_edg.size() > 1) {
        int n = prof_edg.size();
        vector<vector<ll>> new_profedg;
        for (int i = 0; i + 1 < n; i += 2) {
            new_profedg.push_back(merge(prof_edg[i], prof_edg[i + 1]));
        }
        if (n % 2) {
            new_profedg.push_back(prof_edg.back());
        }
        prof_edg = new_profedg;
    }
    return prof_edg.back();
}

signed main() {
    int n, k;
    cin >> n >> k;
    for (int i = 0; i + 1 < n; ++i) {
        int u, v, c;
        cin >> u >> v >> c;
        --u, --v;
        edg[u].push_back({v, c});
        edg[v].push_back({u, c});
    }
    for (int i = 0; i < n; ++i) {
        vector<ll> ans = dfs(i, -1);
        if (k >= ans.size())
            cout << ans.back() << '\n';
        else
            cout << ans[k] << '\n';
    }
}

Compilation message (stderr)

Main.cpp: In function 'std::vector<long long int> dfs(int, int)':
Main.cpp:23:46: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   23 |     if (edg[v].empty() || edg[v].size() == 1 && edg[v][0].first == rt) {
      |                           ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:62:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |         if (k >= ans.size())
      |             ~~^~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 0 / 20
• Subtask 5: 0 / 12
• Subtask 6: 0 / 32