Submission #1124043

#	Time	Username	Problem	Language	Result	Execution time	Memory
1124043		luvna	Harbingers (CEOI09_harbingers)	C++20	20 / 100	1096 ms	11896 KiB

harbingers

#include<bits/stdc++.h>

#define MASK(i) (1 << (i))
#define pub push_back
#define all(v) v.begin(), v.end()
#define compact(v) v.erase(unique(all(v)), end(v))
#define pii pair<int,int>
#define fi first
#define se second
#define endl "\n"
#define sz(v) (int)(v).size()
#define dbg(x) "[" #x " = " << (x) << "]"

using namespace std;

template<class T> bool minimize(T& a, T b){if(a > b) return a = b, true;return false;}
template<class T> bool maximize(T& a, T b){if(a < b) return a = b, true;return false;}

typedef long long ll;
typedef long double ld;

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand(ll l, ll r){return uniform_int_distribution<ll>(l, r)(rng);}

const int N = 2e5 + 15;
const ll INF = 1e18;

int n;
ll dp[N];
int par[N];
vector<pii> g[N];
int wait[N], speed[N];
int h[N];

void dfs(int u, int p){
    if(u > 1){
        int v = par[u];
        while(v){
            minimize(dp[u], 1LL*speed[u]*(h[u] - h[v]) + wait[u] + dp[v]);
            v = par[v];
        }
    }
    for(auto [v, w] : g[u]) if(v != p){
        h[v] = h[u] + w;
        par[v] = u;
        dfs(v,u);
    }
}

void solve(){
    cin >> n;

    for(int i = 1; i < n; i++){
        int u, v, w; cin >> u >> v >> w;
        g[u].pub({v,w});
        g[v].pub({u,w});
    }

    for(int i = 2; i <= n; i++) cin >> wait[i] >> speed[i];

    fill(dp + 1, dp + 1 + n, INF);

    dp[1] = 0;

    dfs(1,-1);

    for(int i = 2; i <= n; i++) cout << dp[i] << " ";
}

signed main(){
    ios_base::sync_with_stdio(NULL);
    cin.tie(0); cout.tie(0);

    #define task "task"

    if(fopen(task".INP", "r")){
        freopen(task".INP", "r", stdin);
        freopen(task".ANS", "w", stdout);
    }

    int t; t = 1; //cin >> t;
    while(t--) solve();
}

Compilation message (stderr)

harbingers.cpp: In function 'int main()':
harbingers.cpp:77:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   77 |         freopen(task".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
harbingers.cpp:78:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   78 |         freopen(task".ANS", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 100