Submission #1236330

#	Time	Username	Problem	Language	Result	Execution time	Memory
1236330		mountainsalt	Harbingers (CEOI09_harbingers)	C++20	0 / 100	3 ms	2632 KiB

harbingers

#include <bits/stdc++.h>
#define int long long
#define emb emplace_back
#define pii pair <int, int>

using namespace std;

const int mod = 1e9 + 7;
const int inf = 1e18;
const int N = 1e5 + 5;

int n, s[N], v[N], dis[N], sz[N], dp[N];
bool visited[N];
vector <pii> adj[N];

int dfssz(int u, int p){
    for (auto [w, v] : adj[u]) {
        if (v == p) continue;
        dis[v] = dis[u] + w;
        sz[u] += dfssz(v, u);
    }
    return sz[u];
}

void dfs(int u, int p){
    if (u != 1) {
        dp[u] = 1e18;
        for (int i = 1; i <= n; i++) {
            if (!visited[i]) continue;
            dp[u] = min(dp[u], dp[i] + s[u] + (dis[u] - dis[i]) * v[u]);
        }
    }
    visited[u] = true;
    for (auto [w, v] : adj[u]) {
        if (v == p) continue;
        dfs(v, u);
    }
    visited[u] = false;
}

signed main(){
    freopen("input.in", "r", stdin);
    freopen("output.out", "w", stdout);
    cin.tie(NULL)->sync_with_stdio(false);
    cin >> n;
    for (int i = 1; i < n; i++) {
        int u, v, w; cin >> u >> v >> w;
        adj[u].emb(w, v);
        adj[v].emb(w, u);
    }
    for (int i = 2; i <= n; i++) {
        cin >> s[i] >> v[i];
    }
    dfssz(1, 1);
    // for (int i = 1; i <= n; i++) {
    //     cout << i << ": " << dis[i] << "\n";
    // }
    dp[1] = 0;
    dfs(1, 1);
    for (int i = 2; i <= n; i++) cout << dp[i] << " ";
}

Compilation message (stderr)

harbingers.cpp: In function 'int main()':
harbingers.cpp:42:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |     freopen("input.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
harbingers.cpp:43:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |     freopen("output.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 100