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Submission #878339

# Submission time Handle Problem Language Result Execution time Memory
878339 2023-11-24T08:28:09 Z hazzu Putovanje (COCI20_putovanje) C++17
110 / 110
 80 ms 25528 KB 
#include <bits/stdc++.h>
#define taskname "A"
using namespace std;

typedef long long ll;
struct Edge {
    int v, c1, c2;
};

class LowestCommonAncestor {
private:
    struct Node { 
        int depth, label;
        Node *parent, *jump;

        Node() {}
        Node(Node *p) {
            parent = p;
            depth = p->depth + 1;
            if (p->depth - p->jump->depth 
                == p->jump->depth - p->jump->jump->depth) {
                jump = p->jump->jump;
            }
            else jump = p; 
        }
    };

    int n;
    vector<Node*> t;
    vector<vector<int>> adj;

public:
    LowestCommonAncestor(int n): n(n), t(n + 1), adj(n + 1) {}

    void add_edge(int u, int v) {
        adj[u].push_back(v);
    }

    void build() {
        t[1] = new Node();
        t[1]->depth = 0;
        t[1]->jump = t[1];
        t[1]->parent = nullptr;
        t[1]->label = 1;
        dfs(1, 1);
    }

    void dfs(int u, int p) {
        for (int v: adj[u]) if (v != p) {
            t[v] = new Node(t[u]);
            t[v]->label = v;
            dfs(v, u);
        }
    }

    int find(int u, int d) {
        Node *pu = t[u];
        while (pu->depth > d) {
            if (pu->jump->depth < d) 
                pu = pu->parent;
            else 
                pu = pu->jump;
        }
        return pu->label;
    }

    int get(int u, int v) {
        if (t[u]->depth < t[v]->depth) swap(u, v);
        u = find(u, t[v]->depth);
        Node *pu = t[u], *pv = t[v];
        
        while (pu != pv) {
            if (pu->jump == pv->jump) {
                pu = pu->parent;
                pv = pv->parent;
            }
            else {
                pu = pu->jump;
                pv = pv->jump;
            }
        }

        return pu->label;
    }
};

void Input() {
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    if (fopen(taskname".inp", "r")) {
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
}

void Solve() {
    int n; cin >> n;

    vector<vector<Edge>> adj(n + 1);
    LowestCommonAncestor lca(n);
    
    for (int i = 1; i < n; i++) {
        int u, v, c1, c2; 
        cin >> u >> v >> c1 >> c2;
        lca.add_edge(u, v);
        lca.add_edge(v, u);
        adj[u].push_back({v, c1, c2});
        adj[v].push_back({u, c1, c2});
    }
    lca.build();

    vector<ll> freq(n + 1, 0);
    for (int i = 2; i <= n; i++) {
        int l = lca.get(i - 1, i);
        freq[i - 1]++;
        freq[i]++;
        freq[l] -= 2;
    }

    ll ans = 0;
    function<void(int, int)> dfs = [&](int u, int p) {
        for (Edge &e: adj[u])
            if (e.v != p) {
                dfs(e.v, u);
                ans += min(freq[e.v] * e.c1, e.c2 * 1ll);
                freq[u] += freq[e.v];
            }
    };
    dfs(1, 1);

    cout << ans;
}

int main(){
    clock_t begin = clock();
    Input();
    Solve();
    cerr << "Time: " << (clock() - begin + 1.0) / CLOCKS_PER_SEC << "s";
    return 0;
}

Compilation message

putovanje.cpp: In function 'void Input()':
putovanje.cpp:91:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   91 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
putovanje.cpp:92:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   92 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 696 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 1 ms 604 KB Output is correct
5 Correct 1 ms 724 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 856 KB Output is correct
9 Correct 1 ms 604 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 66 ms 21072 KB Output is correct
2 Correct 75 ms 22568 KB Output is correct
3 Correct 74 ms 25528 KB Output is correct
4 Correct 80 ms 24656 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 68 ms 20556 KB Output is correct
7 Correct 42 ms 15440 KB Output is correct
8 Correct 70 ms 21076 KB Output is correct
9 Correct 51 ms 21844 KB Output is correct
10 Correct 51 ms 21336 KB Output is correct
11 Correct 58 ms 23156 KB Output is correct
12 Correct 53 ms 23196 KB Output is correct

Subtask #3
65.0 / 65.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 696 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 1 ms 604 KB Output is correct
5 Correct 1 ms 724 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 856 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 66 ms 21072 KB Output is correct
11 Correct 75 ms 22568 KB Output is correct
12 Correct 74 ms 25528 KB Output is correct
13 Correct 80 ms 24656 KB Output is correct
14 Correct 1 ms 604 KB Output is correct
15 Correct 68 ms 20556 KB Output is correct
16 Correct 42 ms 15440 KB Output is correct
17 Correct 70 ms 21076 KB Output is correct
18 Correct 51 ms 21844 KB Output is correct
19 Correct 51 ms 21336 KB Output is correct
20 Correct 58 ms 23156 KB Output is correct
21 Correct 53 ms 23196 KB Output is correct
22 Correct 63 ms 18652 KB Output is correct
23 Correct 61 ms 16468 KB Output is correct
24 Correct 62 ms 18260 KB Output is correct
25 Correct 1 ms 604 KB Output is correct
26 Correct 24 ms 8416 KB Output is correct
27 Correct 49 ms 15956 KB Output is correct
28 Correct 43 ms 19248 KB Output is correct
29 Correct 53 ms 23096 KB Output is correct
30 Correct 54 ms 22752 KB Output is correct
31 Correct 1 ms 604 KB Output is correct