oj.uz

Submission #123451

# Submission time Handle Problem Language Result Execution time Memory
123451 2019-07-01T13:02:50 Z popovicirobert Beads and wires (APIO14_beads) C++14
100 / 100
 371 ms 30312 KB 
#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44


/*const int MOD = ;

inline int lgput(int a, int b) {
    int ans = 1;
    while(b > 0) {
        if(b & 1) ans = (1LL * ans * a) % MOD;
        b >>= 1;
        a = (1LL * a * a) % MOD;
    }
    return ans;
}

inline void mod(int &x) {
    if(x >= MOD)
        x -= MOD;
}

inline void add(int &x, int y) {
    x += y;
    mod(x);
}

inline void sub(int &x, int y) {
    x += MOD - y;
    mod(x);
}


inline void mul(int &x, int y) {
    x = (1LL * x * y) % MOD;
}*/


using namespace std;

const ll INF = 1e15;
const int MAXN = (int) 2e5;

vector < pair <int, int> > g[MAXN + 1];
ll dp[MAXN + 1][2], cst[MAXN + 1];
// dp[nod][0] = nu ai spart nimic
// dp[nod][1] = ai spart un fiu de tata

void dfs(int nod, int par) {
    vector <ll> cur(2, -INF);
    cur[0] = 0;

    for(auto it : g[nod]) {
        if(it.first != par) {
            cst[it.first] = it.second;
            dfs(it.first, nod);

            ll mx = max(dp[it.first][1] + it.second, dp[it.first][0]);
            cur[1] = max(cur[0] + dp[it.first][0] + it.second, cur[1] + mx);
            cur[0] += mx;
        }
    }
    dp[nod][0] = cur[0], dp[nod][1] = cur[1];
}

ll ans;

void solve(int nod, int par) {
    ans = max(ans, dp[nod][0]);

    vector < pair <ll, int> > vals;
    for(auto it : g[nod]) {
        vals.push_back({dp[it.first][0] + it.second - max(dp[it.first][0], dp[it.first][1] + it.second), it.first});
    }
    sort(vals.begin(), vals.end(), greater < pair <ll, int> >());

    for(auto it : g[nod]) {
        if(it.first != par) {
            ll a = dp[nod][0], b = dp[nod][1], c = dp[it.first][0], d = dp[it.first][1];
            ll mx = max(dp[it.first][0], dp[it.first][1] + it.second);

            dp[nod][0] -= mx;
            if(it.first != vals[0].second) {
                dp[nod][1] -= mx;
            }
            else {
                if(vals.size() > 1) {
                    dp[nod][1] -= dp[it.first][0] + it.second;
                    dp[nod][1] += vals[1].first;
                }
                else {
                    dp[nod][1] = -INF;
                }
            }

            mx = max(dp[nod][0], dp[nod][1] + it.second);
            dp[it.first][1] = max(dp[it.first][1] + mx, dp[it.first][0] + dp[nod][0] + it.second);
            dp[it.first][0] += mx;

            solve(it.first, nod);

            dp[nod][0] = a, dp[nod][1] = b, dp[it.first][0] = c, dp[it.first][1] = d;
        }
    }
}

int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, n;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n;

    for(i = 1; i < n; i++) {
        int x, y, z;
        cin >> x >> y >> z;
        g[x].push_back({y, z});
        g[y].push_back({x, z});
    }

    dfs(1, 0);
    solve(1, 0);

    cout << ans;

    //cin.close();
    //cout.close();
    return 0;
}

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5112 KB Output is correct
2 Correct 6 ms 5112 KB Output is correct
3 Correct 6 ms 5116 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 6 ms 5112 KB Output is correct
6 Correct 6 ms 4984 KB Output is correct
7 Correct 6 ms 4984 KB Output is correct
8 Correct 6 ms 5112 KB Output is correct
9 Correct 6 ms 4984 KB Output is correct
10 Correct 6 ms 5112 KB Output is correct
11 Correct 6 ms 4984 KB Output is correct
12 Correct 6 ms 5084 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5112 KB Output is correct
2 Correct 6 ms 5112 KB Output is correct
3 Correct 6 ms 5116 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 6 ms 5112 KB Output is correct
6 Correct 6 ms 4984 KB Output is correct
7 Correct 6 ms 4984 KB Output is correct
8 Correct 6 ms 5112 KB Output is correct
9 Correct 6 ms 4984 KB Output is correct
10 Correct 6 ms 5112 KB Output is correct
11 Correct 6 ms 4984 KB Output is correct
12 Correct 6 ms 5084 KB Output is correct
13 Correct 6 ms 4984 KB Output is correct
14 Correct 6 ms 5112 KB Output is correct
15 Correct 6 ms 5112 KB Output is correct
16 Correct 6 ms 5112 KB Output is correct
17 Correct 6 ms 4984 KB Output is correct
18 Correct 6 ms 4984 KB Output is correct
19 Correct 7 ms 5112 KB Output is correct
20 Correct 6 ms 5028 KB Output is correct
21 Correct 7 ms 4984 KB Output is correct
22 Correct 6 ms 5112 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5112 KB Output is correct
2 Correct 6 ms 5112 KB Output is correct
3 Correct 6 ms 5116 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 6 ms 5112 KB Output is correct
6 Correct 6 ms 4984 KB Output is correct
7 Correct 6 ms 4984 KB Output is correct
8 Correct 6 ms 5112 KB Output is correct
9 Correct 6 ms 4984 KB Output is correct
10 Correct 6 ms 5112 KB Output is correct
11 Correct 6 ms 4984 KB Output is correct
12 Correct 6 ms 5084 KB Output is correct
13 Correct 6 ms 4984 KB Output is correct
14 Correct 6 ms 5112 KB Output is correct
15 Correct 6 ms 5112 KB Output is correct
16 Correct 6 ms 5112 KB Output is correct
17 Correct 6 ms 4984 KB Output is correct
18 Correct 6 ms 4984 KB Output is correct
19 Correct 7 ms 5112 KB Output is correct
20 Correct 6 ms 5028 KB Output is correct
21 Correct 7 ms 4984 KB Output is correct
22 Correct 6 ms 5112 KB Output is correct
23 Correct 10 ms 5368 KB Output is correct
24 Correct 10 ms 5624 KB Output is correct
25 Correct 9 ms 5368 KB Output is correct
26 Correct 16 ms 5880 KB Output is correct
27 Correct 14 ms 5752 KB Output is correct
28 Correct 13 ms 6236 KB Output is correct
29 Correct 13 ms 6008 KB Output is correct
30 Correct 13 ms 6008 KB Output is correct
31 Correct 14 ms 6648 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 5112 KB Output is correct
2 Correct 6 ms 5112 KB Output is correct
3 Correct 6 ms 5116 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 6 ms 5112 KB Output is correct
6 Correct 6 ms 4984 KB Output is correct
7 Correct 6 ms 4984 KB Output is correct
8 Correct 6 ms 5112 KB Output is correct
9 Correct 6 ms 4984 KB Output is correct
10 Correct 6 ms 5112 KB Output is correct
11 Correct 6 ms 4984 KB Output is correct
12 Correct 6 ms 5084 KB Output is correct
13 Correct 6 ms 4984 KB Output is correct
14 Correct 6 ms 5112 KB Output is correct
15 Correct 6 ms 5112 KB Output is correct
16 Correct 6 ms 5112 KB Output is correct
17 Correct 6 ms 4984 KB Output is correct
18 Correct 6 ms 4984 KB Output is correct
19 Correct 7 ms 5112 KB Output is correct
20 Correct 6 ms 5028 KB Output is correct
21 Correct 7 ms 4984 KB Output is correct
22 Correct 6 ms 5112 KB Output is correct
23 Correct 10 ms 5368 KB Output is correct
24 Correct 10 ms 5624 KB Output is correct
25 Correct 9 ms 5368 KB Output is correct
26 Correct 16 ms 5880 KB Output is correct
27 Correct 14 ms 5752 KB Output is correct
28 Correct 13 ms 6236 KB Output is correct
29 Correct 13 ms 6008 KB Output is correct
30 Correct 13 ms 6008 KB Output is correct
31 Correct 14 ms 6648 KB Output is correct
32 Correct 49 ms 8900 KB Output is correct
33 Correct 46 ms 8820 KB Output is correct
34 Correct 55 ms 8888 KB Output is correct
35 Correct 271 ms 20700 KB Output is correct
36 Correct 286 ms 20728 KB Output is correct
37 Correct 371 ms 20728 KB Output is correct
38 Correct 253 ms 25440 KB Output is correct
39 Correct 240 ms 25560 KB Output is correct
40 Correct 244 ms 24560 KB Output is correct
41 Correct 273 ms 30312 KB Output is correct