답안 #389163

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
389163 2021-04-13T18:36:09 Z phathnv 구슬과 끈 (APIO14_beads) C++11
100 / 100
327 ms 35484 KB
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

const int N = 2e5 + 7;
const int INF = 1e9 + 7;

struct Edge{
    int v, c;
    Edge(int _v, int _c){
        v = _v;
        c = _c;
    }
};

int n, down[N][2], up[N][2];
vector<Edge> adj[N];

void Dfs(int u, int p){
    down[u][0] = 0;
    down[u][1] = -INF;
    for(Edge e : adj[u]){
        int v = e.v;
        int c = e.c;
        if (v == p)
            continue;
        Dfs(v, u);
        down[u][1] = max(down[u][1] + max(down[v][0], down[v][1] + c), down[u][0] + down[v][0] + c);
        down[u][0] += max(down[v][0], down[v][1] + c);
    }
}

void Dfs2(int u, int p){
    if (p == -1){
        up[u][0] = 0;
        up[u][1] = -INF;
    }
    int sum = up[u][0];
    multiset<int> s;
    s.insert(up[u][1] - up[u][0]);
    for(Edge e : adj[u]){
        int v = e.v;
        int c = e.c;
        if (v == p)
            continue;
        sum += max(down[v][0], down[v][1] + c);
        s.insert(down[v][0] + c - max(down[v][0], down[v][1] + c));
    }
    for(Edge e : adj[u]){
        int v = e.v;
        int c = e.c;
        if (v == p)
            continue;
        sum -= max(down[v][0], down[v][1] + c);
        s.erase(s.find(down[v][0] + c - max(down[v][0], down[v][1] + c)));
        up[v][0] = sum + max(0, *(--s.end()) + c);
        up[v][1] = sum + c;
        s.insert(down[v][0] + c - max(down[v][0], down[v][1] + c));
        sum += max(down[v][0], down[v][1] + c);
    }

    for(Edge e : adj[u]){
        int v = e.v;
        if (v == p)
            continue;
        Dfs2(v, u);
    }
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    cin >> n;
    for(int i = 1; i < n; i++){
        int u, v, c;
        cin >> u >> v >> c;
        adj[u].push_back(Edge(v, c));
        adj[v].push_back(Edge(u, c));
    }

    Dfs(1, -1);
    Dfs2(1, -1);
    int res = 0;
    for(int i = 1; i <= n; i++)
        res = max(res, up[i][0] + down[i][0]);
    cout << res;

    return 0;
}
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4944 KB Output is correct
2 Correct 3 ms 4940 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 4 ms 4940 KB Output is correct
6 Correct 3 ms 4940 KB Output is correct
7 Correct 3 ms 4940 KB Output is correct
8 Correct 3 ms 4940 KB Output is correct
9 Correct 3 ms 4940 KB Output is correct
10 Correct 3 ms 4940 KB Output is correct
11 Correct 3 ms 4940 KB Output is correct
12 Correct 3 ms 4940 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4944 KB Output is correct
2 Correct 3 ms 4940 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 4 ms 4940 KB Output is correct
6 Correct 3 ms 4940 KB Output is correct
7 Correct 3 ms 4940 KB Output is correct
8 Correct 3 ms 4940 KB Output is correct
9 Correct 3 ms 4940 KB Output is correct
10 Correct 3 ms 4940 KB Output is correct
11 Correct 3 ms 4940 KB Output is correct
12 Correct 3 ms 4940 KB Output is correct
13 Correct 3 ms 4940 KB Output is correct
14 Correct 3 ms 4940 KB Output is correct
15 Correct 3 ms 4940 KB Output is correct
16 Correct 3 ms 4940 KB Output is correct
17 Correct 3 ms 4940 KB Output is correct
18 Correct 3 ms 4940 KB Output is correct
19 Correct 3 ms 4940 KB Output is correct
20 Correct 3 ms 4940 KB Output is correct
21 Correct 3 ms 4940 KB Output is correct
22 Correct 3 ms 4940 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4944 KB Output is correct
2 Correct 3 ms 4940 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 4 ms 4940 KB Output is correct
6 Correct 3 ms 4940 KB Output is correct
7 Correct 3 ms 4940 KB Output is correct
8 Correct 3 ms 4940 KB Output is correct
9 Correct 3 ms 4940 KB Output is correct
10 Correct 3 ms 4940 KB Output is correct
11 Correct 3 ms 4940 KB Output is correct
12 Correct 3 ms 4940 KB Output is correct
13 Correct 3 ms 4940 KB Output is correct
14 Correct 3 ms 4940 KB Output is correct
15 Correct 3 ms 4940 KB Output is correct
16 Correct 3 ms 4940 KB Output is correct
17 Correct 3 ms 4940 KB Output is correct
18 Correct 3 ms 4940 KB Output is correct
19 Correct 3 ms 4940 KB Output is correct
20 Correct 3 ms 4940 KB Output is correct
21 Correct 3 ms 4940 KB Output is correct
22 Correct 3 ms 4940 KB Output is correct
23 Correct 7 ms 5196 KB Output is correct
24 Correct 7 ms 5300 KB Output is correct
25 Correct 7 ms 5196 KB Output is correct
26 Correct 10 ms 5452 KB Output is correct
27 Correct 11 ms 5712 KB Output is correct
28 Correct 13 ms 6068 KB Output is correct
29 Correct 13 ms 6112 KB Output is correct
30 Correct 12 ms 6020 KB Output is correct
31 Correct 12 ms 6956 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4944 KB Output is correct
2 Correct 3 ms 4940 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 4 ms 4940 KB Output is correct
6 Correct 3 ms 4940 KB Output is correct
7 Correct 3 ms 4940 KB Output is correct
8 Correct 3 ms 4940 KB Output is correct
9 Correct 3 ms 4940 KB Output is correct
10 Correct 3 ms 4940 KB Output is correct
11 Correct 3 ms 4940 KB Output is correct
12 Correct 3 ms 4940 KB Output is correct
13 Correct 3 ms 4940 KB Output is correct
14 Correct 3 ms 4940 KB Output is correct
15 Correct 3 ms 4940 KB Output is correct
16 Correct 3 ms 4940 KB Output is correct
17 Correct 3 ms 4940 KB Output is correct
18 Correct 3 ms 4940 KB Output is correct
19 Correct 3 ms 4940 KB Output is correct
20 Correct 3 ms 4940 KB Output is correct
21 Correct 3 ms 4940 KB Output is correct
22 Correct 3 ms 4940 KB Output is correct
23 Correct 7 ms 5196 KB Output is correct
24 Correct 7 ms 5300 KB Output is correct
25 Correct 7 ms 5196 KB Output is correct
26 Correct 10 ms 5452 KB Output is correct
27 Correct 11 ms 5712 KB Output is correct
28 Correct 13 ms 6068 KB Output is correct
29 Correct 13 ms 6112 KB Output is correct
30 Correct 12 ms 6020 KB Output is correct
31 Correct 12 ms 6956 KB Output is correct
32 Correct 45 ms 8432 KB Output is correct
33 Correct 43 ms 8436 KB Output is correct
34 Correct 46 ms 8544 KB Output is correct
35 Correct 259 ms 19012 KB Output is correct
36 Correct 272 ms 19132 KB Output is correct
37 Correct 298 ms 19176 KB Output is correct
38 Correct 324 ms 27956 KB Output is correct
39 Correct 308 ms 28812 KB Output is correct
40 Correct 296 ms 27820 KB Output is correct
41 Correct 327 ms 35484 KB Output is correct