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Submission #538831

# Submission time Handle Problem Language Result Execution time Memory
538831 2022-03-17T21:05:00 Z Lobo Beads and wires (APIO14_beads) C++17
100 / 100
 209 ms 29576 KB 
#include<bits/stdc++.h>
using namespace std;

const long long inf = (long long) 1e18 + 10;
const int inf1 = (int) 1e9 + 10;
#define int long long
#define dbl long double
#define endl '\n'
#define sc second
#define fr first
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()

#define maxn 200020

int n, dp[maxn][2], ans;
pair<int,int> mxv[maxn];
vector<pair<int,int>> g[maxn];

// dp(u,1) ta com azul pro pai e vai ter qual o melhor pra continuar assim
// 

void dfs(int u, int p) {
    int ans1 = 0;
    mxv[u] = mp(-inf,-inf);

    for(auto V : g[u]) {
        int v = V.fr;
        int w = V.sc;
        if(v == p) continue;

        dfs(v,u);
        ans1+= max(dp[v][0],dp[v][1]+w);
        mxv[u].sc = max(mxv[u].sc, dp[v][0] + w - max(dp[v][0],dp[v][1]+w));
        if(mxv[u].sc > mxv[u].fr) swap(mxv[u].fr,mxv[u].sc);
    }



    dp[u][0] = ans1;
    dp[u][1] = ans1+mxv[u].fr;

    // cout << u << " -- " << dp[u][0] << " " << dp[u][1] << endl;
}

void reroot(int u, int p, int wp) {
    //p é a raiz da tree até entao
    //tiro o u do p e insiro o p no u
    int antu0 = dp[u][0];
    int antu1 = dp[u][1];
    int antp0 = dp[p][0];
    int antp1 = dp[p][1];
    pair<int,int> antmxv = mxv[u];

    //tirar u do p
    dp[p][0]-= max(dp[u][0],dp[u][1]+wp);
    if(mxv[p].fr == dp[u][0] + wp - max(dp[u][0],dp[u][1]+wp)) dp[p][1] = dp[p][0]+mxv[p].sc;
    else dp[p][1] = dp[p][0] + mxv[p].fr;

    //insiro p em u
    dp[u][0]+= max(dp[p][0],dp[p][1]+wp);
    mxv[u].sc = max(mxv[u].sc, dp[p][0] + wp - max(dp[p][0],dp[p][1]+wp));
    if(mxv[u].sc > mxv[u].fr) swap(mxv[u].fr,mxv[u].sc);
    dp[u][1] = dp[u][0] + mxv[u].fr;

    ans = max(ans, dp[u][0]);

    for(auto V : g[u]) {
        int v = V.fr;
        int w = V.sc;
        if(v == p) continue;

        reroot(v,u,w);
    }

    //volta as respostas anteriores
    dp[u][0] = antu0;
    dp[u][1] = antu1;
    dp[p][0] = antp0;
    dp[p][1] = antp1;
    mxv[u] = antmxv;

}

void solve() {
    cin >> n;
    for(int i = 1; i < n; i++) {
        int u,v,w; cin >> u >> v >> w;

        g[u].pb(mp(v,w));
        g[v].pb(mp(u,w));
    }

    dfs(1,1);
    ans = dp[1][0];
    for(auto V : g[1]) {
        int v = V.fr;
        int w = V.sc;
        reroot(v,1,w);
    }

    cout << ans << endl;
}

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(0);

    // freopen("in.in", "r", stdin);
    // freopen("out.out", "w", stdout);

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

}

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 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5024 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 5024 KB Output is correct
9 Correct 2 ms 5024 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 4 ms 5024 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 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5024 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 5024 KB Output is correct
9 Correct 2 ms 5024 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 4 ms 5024 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 4 ms 5028 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 5024 KB Output is correct
17 Correct 3 ms 5024 KB Output is correct
18 Correct 3 ms 5024 KB Output is correct
19 Correct 4 ms 4948 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 5032 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5024 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 5024 KB Output is correct
9 Correct 2 ms 5024 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 4 ms 5024 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 4 ms 5028 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 5024 KB Output is correct
17 Correct 3 ms 5024 KB Output is correct
18 Correct 3 ms 5024 KB Output is correct
19 Correct 4 ms 4948 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 5032 KB Output is correct
23 Correct 5 ms 5428 KB Output is correct
24 Correct 6 ms 5420 KB Output is correct
25 Correct 6 ms 5420 KB Output is correct
26 Correct 10 ms 5936 KB Output is correct
27 Correct 10 ms 5932 KB Output is correct
28 Correct 7 ms 5968 KB Output is correct
29 Correct 8 ms 5940 KB Output is correct
30 Correct 7 ms 5936 KB Output is correct
31 Correct 7 ms 6316 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 5024 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 5024 KB Output is correct
9 Correct 2 ms 5024 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 4 ms 5024 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 4 ms 5028 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 5024 KB Output is correct
17 Correct 3 ms 5024 KB Output is correct
18 Correct 3 ms 5024 KB Output is correct
19 Correct 4 ms 4948 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 5032 KB Output is correct
23 Correct 5 ms 5428 KB Output is correct
24 Correct 6 ms 5420 KB Output is correct
25 Correct 6 ms 5420 KB Output is correct
26 Correct 10 ms 5936 KB Output is correct
27 Correct 10 ms 5932 KB Output is correct
28 Correct 7 ms 5968 KB Output is correct
29 Correct 8 ms 5940 KB Output is correct
30 Correct 7 ms 5936 KB Output is correct
31 Correct 7 ms 6316 KB Output is correct
32 Correct 33 ms 9804 KB Output is correct
33 Correct 28 ms 9868 KB Output is correct
34 Correct 28 ms 9812 KB Output is correct
35 Correct 209 ms 24992 KB Output is correct
36 Correct 209 ms 25000 KB Output is correct
37 Correct 197 ms 25144 KB Output is correct
38 Correct 124 ms 24240 KB Output is correct
39 Correct 139 ms 24092 KB Output is correct
40 Correct 119 ms 24268 KB Output is correct
41 Correct 175 ms 29576 KB Output is correct