#include <bits/stdc++.h>
using namespace std;
const int maxn = 101010;
vector<int>adj[maxn];
int pa[maxn], sz[maxn];
void dfs(int i, int p)
{
if (p != 0)
adj[i].erase(find(adj[i].begin(), adj[i].end(), p));
pa[i] = p;
sz[i] = 1;
pair<int, int>mx = { -1, -1};
for (int t = 0; t < (int)adj[i].size(); t++)
{
int j = adj[i][t];
dfs(j, i);
sz[i] += sz[j];
mx = max(mx, {sz[j], t});
}
if (mx.second != -1)
swap(adj[i][0], adj[i][mx.second]);
}
int timer = 1;
int nr[maxn], head[maxn], tail[maxn];
void hld(int i, int h)
{
nr[i] = timer++;
head[i] = h;
tail[h] = i;
for (int t = 0; t < (int)adj[i].size(); t++)
{
int j = adj[i][t];
hld(j, t == 0 ? h : j);
}
}
struct line
{
int cc = 0, cd = maxn, dd = 0, dc = maxn;
line() {}
int mn(int c)
{
if (c)
return min({cd, cc, dc + 1, dd + 1});
else
return min({cd + 1, cc + 1, dc, dd});
}
};
line merge(line a, line b)
{
line c;
c.cc = min({a.cc + b.cc, a.cc + b.dc + 1, a.cd + b.cc + 1, a.cd + b.dc});
c.cd = min({a.cc + b.cd, a.cc + b.dd + 1, a.cd + b.cd + 1, a.cd + b.dd});
c.dd = min({a.dc + b.cd, a.dc + b.dd + 1, a.dd + b.cd + 1, a.dd + b.dd});
c.dc = min({a.dc + b.cc, a.dc + b.dc + 1, a.dd + b.cc + 1, a.dd + b.dc});
return c;
}
struct ST
{
line X;
int l, r;
ST *left, *right;
ST(int l, int r): l(l), r(r)
{
if (l < r)
{
left = new ST(l, (l + r) / 2);
right = new ST((l + r) / 2 + 1, r);
X = merge(left->X, right->X);
}
}
line get(int x, int y)
{
if (x <= l && r <= y)
return X;
if (r < x || y < l)
return line();
return merge(left->get(x, y), right->get(x, y));
}
void set(int x, int w, int c)
{
if (l == r)
{
if (c)
X.cc = w;
else
X.dd = w;
}
else
{
if (x <= (l + r) / 2)
left->set(x, w, c);
else
right->set(x, w, c);
X = merge(left->X, right->X);
}
}
} medis(0, 101010);
void initialize(int N, vector<int> A, vector<int> B)
{
for (int i = 0; i < N - 1; i++)
{
adj[A[i]].push_back(B[i]);
adj[B[i]].push_back(A[i]);
}
dfs(1, 0);
hld(1, 1);
}
int C[maxn], D[maxn], V[maxn];
int fix(int v, int p)
{
V[v] = p;
while (true)
{
int w = head[v];
line X = medis.get(nr[w], nr[tail[w]]);
C[pa[w]] -= X.mn(1);
D[pa[w]] -= X.mn(0);
medis.set(nr[v], V[v] == 1 ? maxn : C[v], 0);
medis.set(nr[v], V[v] == -1 ? maxn : D[v], 1);
X = medis.get(nr[w], nr[tail[w]]);
C[pa[w]] += X.mn(1);
D[pa[w]] += X.mn(0);
if (v == 1)break;
if (v != w)
v = w;
else
v = pa[v];
}
return min(C[0], D[0]);
}
int cat(int v)
{
return fix(v, -1);
}
int dog(int v)
{
return fix(v, 1);
}
int neighbor(int v)
{
return fix(v, 0);
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
18 ms |
12152 KB |
Output is correct |
| 2 |
Incorrect |
18 ms |
12152 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
18 ms |
12152 KB |
Output is correct |
| 2 |
Incorrect |
18 ms |
12152 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
18 ms |
12152 KB |
Output is correct |
| 2 |
Incorrect |
18 ms |
12152 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
