Submission #637628

#	Time	Username	Problem	Language	Result	Execution time	Memory
637628		4EVER	Putovanje (COCI20_putovanje)	C++11	110 / 110	136 ms	23464 KiB

putovanje

#include <bits/stdc++.h>
using namespace std;

int n;
vector<pair<int, int>> adj[200001];
int val[200001], cnt[200001], depth[200001], c[200001], d[200001];
int spt[19][200001];

void DFS(int u = 1, int par = -1){
    for(auto x : adj[u]){
        int v = x.first;
        if(v == par) continue;
        depth[v] = depth[u] + 1;
        spt[0][v] = u;
        for(int i = 1; i <= 18; i++) spt[i][v] = spt[i - 1][spt[i - 1][v]];
        DFS(v, u);
    }
}

int LCA(int u, int v){
    if(depth[u] < depth[v]) swap(u, v);
    int k = depth[u] - depth[v];
    for(int i = 18; i >= 0; i--) if((k >> i) & 1) u = spt[i][u];
    if(u == v) return u;
    for(int i = 18; i >= 0; i--) if(spt[i][u] != spt[i][v]){
        u = spt[i][u];
        v = spt[i][v];
    }
    return spt[0][u];
}

void reDFS(int u = 1, int par = -1, int id = -1){
    for(auto x : adj[u]){
        int v = x.first;
        int w = x.second;
        if(v == par) continue;
        reDFS(v, u, w);
        val[u] += val[v];
    }
    if(id != -1) cnt[id] = val[u];
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    #define TASK "PUTOVANJE"
    if(fopen(TASK".inp", "r")) {
        freopen(TASK".inp", "r", stdin);
        freopen(TASK".out", "w", stdout);
    }
    cin >> n;
    for(int i = 1; i < n; i++){
        int u, v; cin >> u >> v;
        cin >> c[i] >> d[i];
        adj[u].push_back({v, i});
        adj[v].push_back({u, i});
    }
    DFS();
    for(int i = 2; i <= n; i++){
        val[i]++;
        val[i - 1]++;
        val[LCA(i, i - 1)] -= 2;
    }
    reDFS();
    long long res = 0;
    for(int i = 1; i < n; i++){
        res += min((long long) c[i] * cnt[i], (long long) d[i]);
    }
    cout << res;
    return 0;
}

Compilation message (stderr)

putovanje.cpp: In function 'int main()':
putovanje.cpp:47:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |         freopen(TASK".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
putovanje.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen(TASK".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 25 / 25
• Subtask 3: 65 / 65