#include <bits/stdc++.h>
using namespace std;
template<typename T>
bool maximize(T& a, const T& b){
if(a < b){
return a = b, true;
} return false;
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
#ifdef LOCAL
freopen("task.inp", "r", stdin);
freopen("task.out", "w", stdout);
#endif // LOCAL
struct DisjointSet{
vector<int> lab;
DisjointSet(int n) : lab(n, -1) {}
int root(int u){
return lab[u] < 0 ? u : (lab[u] = root(lab[u]));
}
bool unite(int u, int v){
u = root(u);
v = root(v);
if(u == v) return false;
if(lab[u] > lab[v]) swap(u, v);
lab[u] += lab[v];
lab[v] = u;
return true;
}
};
int N;
cin >> N;
vector<int> P(N);
for(int i = 0; i < N; ++i) cin >> P[i], --P[i];
vector<vector<int>> adj(N);
for(int i = 1; i < N; ++i){
int u, v;
cin >> u >> v;
--u, --v;
u = P[u];
v = P[v];
adj[u].push_back(v);
adj[v].push_back(u);
}
int timerdfs = 0;
vector<int> depth(N);
vector<int> tin(N), tout(N);
vector<vector<int>> lift(32 - __builtin_clz(N), vector<int>(N));
function<void(int, int)> dfs = [&](int u, int pre){
tin[u] = ++timerdfs;
for(int v : adj[u]) if(v != pre){
depth[v] = depth[u] + 1;
lift[0][v] = u;
for(int i = 1; (1 << i) <= depth[v]; ++i)
lift[i][v] = lift[i - 1][lift[i - 1][v]];
dfs(v, u);
}
tout[u] = timerdfs;
};
auto inside = [&](int u, int v) -> bool{
return tin[u] <= tin[v] && tout[v] <= tout[u];
};
auto getLCA = [&](int u, int v) -> int{
if(inside(u, v)) return u;
if(inside(v, u)) return v;
for(int i = 31 - __builtin_clz(depth[u]); i >= 0; --i){
if(depth[u] >= (1 << i) && !inside(lift[i][u], v)){
u = lift[i][u];
}
}
return lift[0][u];
};
auto distance = [&](int u, int v) -> int{
return depth[u] + depth[v] - 2 * depth[getLCA(u, v)];
};
dfs(N - 1, -1);
vector<int> dp(N), maxLabel(N);
iota(maxLabel.begin(), maxLabel.end(), 0);
DisjointSet dsu(N);
for(int i = 1; i < N; ++i){
for(int j : adj[i]) if(j < i){
int mx = maxLabel[dsu.root(j)];
maximize(dp[i], dp[mx] + distance(mx, i));
dsu.unite(i, j);
maxLabel[dsu.root(i)] = i;
}
}
cout << dp[N - 1] << '\n';
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
456 KB |
Output is correct |
4 |
Correct |
1 ms |
504 KB |
Output is correct |
5 |
Correct |
1 ms |
336 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
1 ms |
456 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
456 KB |
Output is correct |
4 |
Correct |
1 ms |
504 KB |
Output is correct |
5 |
Correct |
1 ms |
336 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
1 ms |
456 KB |
Output is correct |
11 |
Correct |
1 ms |
336 KB |
Output is correct |
12 |
Correct |
1 ms |
336 KB |
Output is correct |
13 |
Correct |
1 ms |
336 KB |
Output is correct |
14 |
Correct |
1 ms |
464 KB |
Output is correct |
15 |
Correct |
1 ms |
336 KB |
Output is correct |
16 |
Correct |
1 ms |
508 KB |
Output is correct |
17 |
Correct |
1 ms |
336 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
456 KB |
Output is correct |
4 |
Correct |
1 ms |
504 KB |
Output is correct |
5 |
Correct |
1 ms |
336 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
1 ms |
456 KB |
Output is correct |
11 |
Correct |
1 ms |
336 KB |
Output is correct |
12 |
Correct |
1 ms |
336 KB |
Output is correct |
13 |
Correct |
1 ms |
336 KB |
Output is correct |
14 |
Correct |
1 ms |
464 KB |
Output is correct |
15 |
Correct |
1 ms |
336 KB |
Output is correct |
16 |
Correct |
1 ms |
508 KB |
Output is correct |
17 |
Correct |
1 ms |
336 KB |
Output is correct |
18 |
Correct |
3 ms |
1616 KB |
Output is correct |
19 |
Correct |
3 ms |
1576 KB |
Output is correct |
20 |
Correct |
4 ms |
1616 KB |
Output is correct |
21 |
Correct |
3 ms |
1360 KB |
Output is correct |
22 |
Correct |
4 ms |
1360 KB |
Output is correct |
23 |
Correct |
4 ms |
1236 KB |
Output is correct |
24 |
Correct |
4 ms |
1360 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
456 KB |
Output is correct |
4 |
Correct |
1 ms |
504 KB |
Output is correct |
5 |
Correct |
1 ms |
336 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
1 ms |
456 KB |
Output is correct |
11 |
Correct |
1 ms |
336 KB |
Output is correct |
12 |
Correct |
1 ms |
336 KB |
Output is correct |
13 |
Correct |
1 ms |
336 KB |
Output is correct |
14 |
Correct |
1 ms |
464 KB |
Output is correct |
15 |
Correct |
1 ms |
336 KB |
Output is correct |
16 |
Correct |
1 ms |
508 KB |
Output is correct |
17 |
Correct |
1 ms |
336 KB |
Output is correct |
18 |
Correct |
3 ms |
1616 KB |
Output is correct |
19 |
Correct |
3 ms |
1576 KB |
Output is correct |
20 |
Correct |
4 ms |
1616 KB |
Output is correct |
21 |
Correct |
3 ms |
1360 KB |
Output is correct |
22 |
Correct |
4 ms |
1360 KB |
Output is correct |
23 |
Correct |
4 ms |
1236 KB |
Output is correct |
24 |
Correct |
4 ms |
1360 KB |
Output is correct |
25 |
Correct |
1 ms |
336 KB |
Output is correct |
26 |
Correct |
3 ms |
1360 KB |
Output is correct |
27 |
Correct |
3 ms |
1360 KB |
Output is correct |
28 |
Correct |
3 ms |
1572 KB |
Output is correct |
29 |
Correct |
3 ms |
1360 KB |
Output is correct |
30 |
Correct |
3 ms |
1104 KB |
Output is correct |
31 |
Correct |
3 ms |
1104 KB |
Output is correct |
32 |
Correct |
3 ms |
1104 KB |
Output is correct |
33 |
Correct |
3 ms |
1104 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
456 KB |
Output is correct |
4 |
Correct |
1 ms |
504 KB |
Output is correct |
5 |
Correct |
1 ms |
336 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
1 ms |
456 KB |
Output is correct |
11 |
Correct |
1 ms |
336 KB |
Output is correct |
12 |
Correct |
1 ms |
336 KB |
Output is correct |
13 |
Correct |
1 ms |
336 KB |
Output is correct |
14 |
Correct |
1 ms |
464 KB |
Output is correct |
15 |
Correct |
1 ms |
336 KB |
Output is correct |
16 |
Correct |
1 ms |
508 KB |
Output is correct |
17 |
Correct |
1 ms |
336 KB |
Output is correct |
18 |
Correct |
3 ms |
1616 KB |
Output is correct |
19 |
Correct |
3 ms |
1576 KB |
Output is correct |
20 |
Correct |
4 ms |
1616 KB |
Output is correct |
21 |
Correct |
3 ms |
1360 KB |
Output is correct |
22 |
Correct |
4 ms |
1360 KB |
Output is correct |
23 |
Correct |
4 ms |
1236 KB |
Output is correct |
24 |
Correct |
4 ms |
1360 KB |
Output is correct |
25 |
Incorrect |
100 ms |
53440 KB |
Output isn't correct |
26 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
460 KB |
Output is correct |
3 |
Correct |
99 ms |
34616 KB |
Output is correct |
4 |
Correct |
102 ms |
34620 KB |
Output is correct |
5 |
Correct |
115 ms |
34628 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
456 KB |
Output is correct |
4 |
Correct |
1 ms |
504 KB |
Output is correct |
5 |
Correct |
1 ms |
336 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
1 ms |
336 KB |
Output is correct |
10 |
Correct |
1 ms |
456 KB |
Output is correct |
11 |
Correct |
1 ms |
336 KB |
Output is correct |
12 |
Correct |
1 ms |
336 KB |
Output is correct |
13 |
Correct |
1 ms |
336 KB |
Output is correct |
14 |
Correct |
1 ms |
464 KB |
Output is correct |
15 |
Correct |
1 ms |
336 KB |
Output is correct |
16 |
Correct |
1 ms |
508 KB |
Output is correct |
17 |
Correct |
1 ms |
336 KB |
Output is correct |
18 |
Correct |
3 ms |
1616 KB |
Output is correct |
19 |
Correct |
3 ms |
1576 KB |
Output is correct |
20 |
Correct |
4 ms |
1616 KB |
Output is correct |
21 |
Correct |
3 ms |
1360 KB |
Output is correct |
22 |
Correct |
4 ms |
1360 KB |
Output is correct |
23 |
Correct |
4 ms |
1236 KB |
Output is correct |
24 |
Correct |
4 ms |
1360 KB |
Output is correct |
25 |
Correct |
1 ms |
336 KB |
Output is correct |
26 |
Correct |
3 ms |
1360 KB |
Output is correct |
27 |
Correct |
3 ms |
1360 KB |
Output is correct |
28 |
Correct |
3 ms |
1572 KB |
Output is correct |
29 |
Correct |
3 ms |
1360 KB |
Output is correct |
30 |
Correct |
3 ms |
1104 KB |
Output is correct |
31 |
Correct |
3 ms |
1104 KB |
Output is correct |
32 |
Correct |
3 ms |
1104 KB |
Output is correct |
33 |
Correct |
3 ms |
1104 KB |
Output is correct |
34 |
Incorrect |
100 ms |
53440 KB |
Output isn't correct |
35 |
Halted |
0 ms |
0 KB |
- |