Submission #965341

#	Time	Username	Problem	Language	Result	Execution time	Memory
965341		MisterReaper	Harbingers (CEOI09_harbingers)	C++17	0 / 100	4 ms	4956 KiB

harbingers

#include <bits/stdc++.h>
using i64 = long long;

constexpr int maxN = 1E5 + 5;
constexpr i64 INF = 1E18;

int N;
std::vector<std::pair<int, int>> adj[maxN];
int S[maxN], V[maxN], par[maxN], D[maxN];
i64 dp[maxN];

void dfs(int v) {
    [&] {
        int u = v;
        while(u != 1) {
            u = par[u];
            // std::cerr << u << ' ' << v << ' ' << dp[u] + 1LL * D[u] * V[v] + S[v] << '\n';
            dp[v] = std::min(dp[v], dp[u] + 1LL * (D[v] - D[u]) * V[v] + S[v]);
        }
    }();

    for(auto [u, w] : adj[v]) {
        if(u == par[v]) {
            continue;
        }
        D[u] = D[v] + w;
        par[u] = v;
        dfs(u);
    }
}

signed main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    #ifndef LOCAL
        freopen("harbingers.in", "r", stdin);
        freopen("harbingers.out", "w", stdout);
    #endif

    std::cin >> N;
    for(int i = 1; i <= N - 1; i++) {
        int A, B, W;
        std::cin >> A >> B >> W;
        adj[A].emplace_back(B, W);
        adj[B].emplace_back(A, W);
    }

    for(int i = 2; i <= N; i++) {
        std::cin >> S[i] >> V[i];
    }

    std::fill_n(&dp[1], N, INF);
    dp[1] = 0;
    par[1] = 1;
    dfs(1);

    for(int i = 2; i <= N; i++) {
        std::cout << dp[i] << ' ';
    }
    std::cout << '\n';

    return 0;
}

Compilation message (stderr)

harbingers.cpp: In function 'int main()':
harbingers.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen("harbingers.in", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
harbingers.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen("harbingers.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 100