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Submission #581016

# Submission time Handle Problem Language Result Execution time Memory
581016 2022-06-22T08:18:52 Z 박상훈(#8359) Beads and wires (APIO14_beads) C++17
28 / 100
 1000 ms 5332 KB 
#include <bits/stdc++.h>

typedef long long ll;
using namespace std;
vector<pair<int, int>> adj[200200];
int dp[200200][2];

void dfs(int s, int pa = -1, int w0 = 0){
    int tmp = -1e9;
    dp[s][0] = 0;
    for (auto &[v, w]:adj[s]) if (v!=pa){
        dfs(v, s, w);
        tmp = max(tmp, dp[v][0] + w - dp[v][1]);
        dp[s][0] += dp[v][1];
    }

    if (w0+tmp>0) dp[s][1] = dp[s][0] + w0 + tmp;
    else dp[s][1] = dp[s][0];
    //if (C.size()>=2) dp[s][0] = max(dp[s][0], dp[s][0] + C[0] + C[1]);

    //printf("%d: %d %d\n", s, dp[s][0], dp[s][1]);
}

int main(){
    int n;
    scanf("%d", &n);
    for (int i=0;i<n-1;i++){
        int x, y, z;
        scanf("%d %d %d", &x, &y, &z);
        adj[x].emplace_back(y, z);
        adj[y].emplace_back(x, z);
    }
    int ans = 0;
    for (int i=1;i<=n;i++){
        dfs(i);
        ans = max(ans, dp[i][0]);
    }
    printf("%d\n", ans);
    return 0;
}

/*
struct Edge{
    int s, w;
    Edge(){}
    Edge(int _s, int _w): s(_s), w(_w) {}
};
int n;

void _remove(vector<vector<Edge>> &adj, int x, int y){
    for (auto iter = adj[x].begin();iter!=adj[x].end();iter++) if (iter->s==y) {adj[x].erase(iter); break;}
    for (auto iter = adj[y].begin();iter!=adj[y].end();iter++) if (iter->s==x) {adj[y].erase(iter); break;}
}

int bct(vector<vector<Edge>> adj){
    bool flag = 0;
    for (int i=1;i<=n;i++) if (!adj[i].empty()) flag = 1;
    if (!flag) return 0;
    int ret = 0;

    for (int i=1;i<=n;i++){
        if (adj[i].size()==1){
            vector<vector<Edge>> nxt = adj;
            _remove(nxt, i, adj[i][0].s);
            ret = max(ret, bct(nxt));
        }
        else if (adj[i].size()==2 && adj[i][0].w > 0 && adj[i][1].w > 0){
            vector<vector<Edge>> nxt = adj;
            int tmp = adj[i][0].w + adj[i][1].w;
            _remove(nxt, i, adj[i][0].s);
            _remove(nxt, i, adj[i][1].s);
            nxt[adj[i][0].s].emplace_back(adj[i][1].s, -1);
            nxt[adj[i][1].s].emplace_back(adj[i][0].s, -1);

            ret = max(ret, bct(nxt) + tmp);
        }
    }
    return ret;
}

int main(){
    scanf("%d", &n);

    vector<vector<Edge>> adj(n+1, vector<Edge>());
    for (int i=0;i<n-1;i++){
        int x, y, z;
        scanf("%d %d %d", &x, &y, &z);
        adj[x].emplace_back(y, z);
        adj[y].emplace_back(x, z);
    }
    printf("%d\n", bct(adj));
}




*/

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:26:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~
beads.cpp:29:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |         scanf("%d %d %d", &x, &y, &z);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 5008 KB Output is correct
3 Correct 3 ms 4960 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 5008 KB Output is correct
3 Correct 3 ms 4960 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 4960 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 4948 KB Output is correct

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 5008 KB Output is correct
3 Correct 3 ms 4960 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 4960 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 4948 KB Output is correct
23 Correct 532 ms 5212 KB Output is correct
24 Correct 447 ms 5208 KB Output is correct
25 Correct 431 ms 5216 KB Output is correct
26 Execution timed out 1098 ms 5332 KB Time limit exceeded
27 Halted 0 ms 0 KB -

Subtask #4
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 5008 KB Output is correct
3 Correct 3 ms 4960 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 4960 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 4948 KB Output is correct
23 Correct 532 ms 5212 KB Output is correct
24 Correct 447 ms 5208 KB Output is correct
25 Correct 431 ms 5216 KB Output is correct
26 Execution timed out 1098 ms 5332 KB Time limit exceeded
27 Halted 0 ms 0 KB -