oj.uz

Submission #940847

# Submission time Handle Problem Language Result Execution time Memory
940847 2024-03-07T18:42:22 Z sysia Beads and wires (APIO14_beads) C++17
100 / 100
 163 ms 38080 KB 
//Sylwia Sapkowska
#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
using namespace std;

void __print(int x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << "'" << x << "'";}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef LOCAL
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

#define int long long
typedef pair<int, int> T;
const int oo = 1e18, oo2 = 1e9+7, K = 30;
const int mod = 998244353;

void solve(){
    int n; cin >> n;
    vector<vector<T>>g(n+1);
    for (int i = 1; i<n; i++){
        int a, b, c; cin >> a >> b >> c;
        g[a].emplace_back(b, c);
        g[b].emplace_back(a, c);
    }
    //pomiedzy kazda para wisienek sciezka laczaca ich srodki musi przechodzic przez inny wierzcholek jakiejs wisienki jeszcze
    //dp[v][0] -> jest wisienka w poddrzewie, nie uzywamy krawedzi do rodzica
    //dp[v][1] -> jest wisienka w poddrzewie, uzywamy krawedzi do rodzica
    //dp[v][2] -> nie ma wisienki w poddrzewie, nie uzywamy krawedzi do rodzica
    //dp[v][3] -> nie ma wisienki w poddrzewie, uzywamy krawedz do rodzica
    vector dp(n+1, vector<int>(4));
    function<void(int, int, int)>dfs = [&](int v, int pa, int cc){
        for (auto [x, c]: g[v]){
            if (x == pa) continue;
            dfs(x, v, c);
            dp[v][2] += max(dp[x][2], dp[x][3]);
        }
        for (auto [x, c]: g[v]){
            dp[v][0] = max(dp[v][0], dp[v][2]+max(dp[x][0], dp[x][1])-max(dp[x][2], dp[x][3]));
        }
        //dp[v][0] -> robimy wisienke w wierzcholku v -> maksymalnie jeden syn wisienki moze miec dp[x][0]
        //dp[v][0] = dp[v][2] + [dp[x][0] - max(dp[x][2], dp[x][3]) + c1] + [dp[x][2]-max(dp[x][2], dp[x][3]) + c2]        
        
        //dp[v][1] -> 1) dp[v][2] + [dp[x][0] - max(dp[x][2], dp[x][3]) + c] + cc (gdy ta jedna wisienka w poddrzewie x)
        //lub dp[v][2] + [dp[x][2] - max(dp[x][2], dp[x][3]) + c] + cc + [max(dp[x][0], dp[x][1]) - max(dp[x][2], dp[x][3])];
        vector<T>mx(2, {-oo, -oo});
        for (auto [x2, c2]: g[v]){
            if (x2 == pa) continue;
            T val = {dp[x2][2]-max(dp[x2][2], dp[x2][3]) + c2, x2};
            if (val >= mx[0]) swap(val, mx[0]);
            if (val >= mx[1]) swap(val, mx[1]);
        }
        for (auto [x1, c1]: g[v]){
            if (x1 == pa) continue;
            dp[v][1] = max(dp[v][1], dp[v][2] + (dp[x1][0] - max(dp[x1][2], dp[x1][3]) + c1) + cc);
            dp[v][0] = max(dp[v][0], 
                dp[v][2] + (dp[x1][0] - max(dp[x1][2], dp[x1][3]) +c1) + (mx[0].second == x1 ? mx[1].first : mx[0].first));
            // for (auto [x2, c2]: g[v]){
                // if (x2 == pa || x2 == x1) continue;
                
                //tu uzywam tego rozroznienia zeby moc uzyc faktu ze nie ma krawedzi do rodzica
                // dp[v][1] = max(dp[v][1], 
                // dp[v][2] + (dp[x1][2] - max(dp[x1][2], dp[x1][3]) + c1) + cc + (max(dp[x2][0], dp[x2][1]) - max(dp[x2][2], dp[x2][3]))); -> nie moge tego uzyc bo powstaje polaczenie pomiedzy srodkami pionowej i w poddrzewie wisienki
            // }
        }
        //dp[v][3] = dp[v][2] + cc + [dp[x][2] - max(dp[x][2], dp[x][3]) + c]
        for (auto [x, c]: g[v]){
            if (x == pa) continue;
            dp[v][3] = max(dp[v][3], dp[v][2]+cc+dp[x][2]-max(dp[x][2], dp[x][3])+c);
        }
        debug(v, dp[v]);
    };
    dfs(1, 1, -oo);    
    cout << max(dp[1][0], dp[1][2]) << "\n";
}

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

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

    return 0;
}

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 456 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 456 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 456 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 456 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 344 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 456 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 456 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 344 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 3 ms 1376 KB Output is correct
24 Correct 2 ms 1116 KB Output is correct
25 Correct 2 ms 1116 KB Output is correct
26 Correct 5 ms 1884 KB Output is correct
27 Correct 4 ms 1884 KB Output is correct
28 Correct 4 ms 2008 KB Output is correct
29 Correct 4 ms 1884 KB Output is correct
30 Correct 4 ms 2000 KB Output is correct
31 Correct 5 ms 2396 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 456 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 456 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 344 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 3 ms 1376 KB Output is correct
24 Correct 2 ms 1116 KB Output is correct
25 Correct 2 ms 1116 KB Output is correct
26 Correct 5 ms 1884 KB Output is correct
27 Correct 4 ms 1884 KB Output is correct
28 Correct 4 ms 2008 KB Output is correct
29 Correct 4 ms 1884 KB Output is correct
30 Correct 4 ms 2000 KB Output is correct
31 Correct 5 ms 2396 KB Output is correct
32 Correct 21 ms 8280 KB Output is correct
33 Correct 21 ms 8284 KB Output is correct
34 Correct 23 ms 8540 KB Output is correct
35 Correct 147 ms 32848 KB Output is correct
36 Correct 163 ms 33092 KB Output is correct
37 Correct 131 ms 32852 KB Output is correct
38 Correct 123 ms 32376 KB Output is correct
39 Correct 133 ms 32020 KB Output is correct
40 Correct 119 ms 32252 KB Output is correct
41 Correct 153 ms 38080 KB Output is correct