# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
253905 | IgorI | Cats or Dogs (JOI18_catdog) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int INF = 1e9;
const int N = 100002;
struct Table{
int a00, a01, a10, a11;
};
Table Merge(Table &A, Table &B)
{
Table S;
S.a00 = min(min(A.a00 + B.a00, A.a01 + B.a10), min(A.a00 + B.a10, A.a01 + B.a00) + 1);
S.a01 = min(min(A.a00 + B.a01, A.a01 + B.a11), min(A.a00 + B.a11, A.a01 + B.a01) + 1);
S.a11 = min(min(A.a10 + B.a01, A.a11 + B.a11), min(A.a10 + B.a11, A.a11 + B.a01) + 1);
S.a10 = min(min(A.a10 + B.a00, A.a11 + B.a10), min(A.a10 + B.a10, A.a11 + B.a00) + 1);
}
struct Sollution{
vector<Table> tree;
void build(int L, int R, int V)
{
if (L + 1 == R)
{
tree[V].a[0][0] = 0;
tree[V].a[0][1] = INF;
tree[V].a[1][0] = INF;
tree[V].a[1][1] = 0;
return;
}
tree[V].a[0][0] = 0;
tree[V].a[1][0] = 1;
tree[V].a[0][1] = 1;
tree[V].a[1][1] = 0;
int M = (L + R) / 2;
build(L, M, 2 * V + 1);
build(M, R, 2 * V + 2);
}
Sollution(int _n)
{
tree.resize(4 * _n);
build(0, _n, 0);
}
void __Change(int pos, int cost0, int cost1, int L, int R, int V)
{
if (L + 1 == R)
{
tree[V].a[0][0] += cost0;
tree[V].a[1][1] += cost1;
return;
}
int M = (L + R) / 2;
if (pos < M) __Change(pos, cost0, cost1, L, M, 2 * V + 1);
else __Change(pos, cost0, cost1, M, R, 2 * V + 2);
tree[V] = Merge(tree[2 * V + 1], tree[2 * V + 2]);
}
void Change(int pos, int cost0, int cost1)
{
__Change(pos, cost0, cost1, 0, tree.size() / 4, 0);
}
Table Cost()
{
return tree[0];
}
};
ll n;
vector<int> graph[N];
ll x[N];
ll papa[N];
ll sz[N];
int main_child[N];
vector<int> other_child[N];
vector<vector<int> > route;
vector<Sollution> hld;
int route_pos[N];
int route_id[N];
void dfs1(int v, int p)
{
papa[v] = p;
sz[v] = 1;
for (auto u : graph[v]) if (u != p)
{
dfs1(u, v);
sz[v] += sz[u];
}
}
void dfs2(int v, int p)
{
int mxsz = 0, id = -1;
for (auto u : graph[v]) if (u != p)
{
if (sz[u] > mxsz)
{
mxsz = sz[u];
id = u;
}
}
main_child[v] = id;
for (auto u : graph[v]) if (u != p)
{
dfs2(u, v);
if (u != id) other_child[v].push_back(u);
}
}
int answer()
{
int x = INF;
Table T = hld[0].Cost();
for (int i = 0; i < 2; i++)
{
for (int j = 0; j < 2; j++)
{
x = min(x, T.a[i][j]);
}
}
return x;
}
void initialize(int n0, vector<int> a, vector<int> b)
{
n = n0;
for (int i = 0; i < n - 1; i++)
{
a[i]--, b[i]--;
graph[a[i]].push_back(b[i]);
graph[b[i]].push_back(a[i]);
}
for (int i = 0; i < n; i++)
{
x[i] = -1;
}
dfs1(0, 0);
dfs2(0, 0);
for (int i = 0; i < n; i++)
{
route_id[i] = -1;
route_pos[i] = -1;
}
for (int i = 0; i < n; i++)
{
if (route_id[i] == -1)
{
vector<int> r;
int x = i;
while (x != -1)
{
r.push_back(x);
x = main_child[x];
}
for (int j = 0; j < r.size(); j++)
{
route_id[r[j]] = route.size();
route_pos[r[j]] = j;
}
route.push_back(r);
hld.push_back(Sollution(r.size()));
}
}
}
void Change(int v, int cost0, int cost1)
{
int x = route_id[v];
int y = route_pos[v];
Table oldT = hld[x].Cost();
int oldminc0 = min(oldT.a[0][0], oldT.a[0][1]);
int oldminc1 = min(oldT.a[1][0], oldT.a[1][1]);
int oldd0 = min(oldminc0, oldminc1 + 1);
int oldd1 = min(oldminc0 + 1, oldminc1);
hld[x].Change(y, cost0, cost1);
Table T = hld[x].Cost();
int minc0 = min(T.a[0][0], T.a[0][1]);
int minc1 = min(T.a[1][0], T.a[1][1]);
int d0 = min(minc0, minc1 + 1);
int d1 = min(minc0 + 1, minc1);
v = route[x][0];
if (v == 0) return;
v = papa[v];
Change(v, d0 - oldd0, d1 - oldd1);
}
int cat(int v)
{
v--;
x[v] = 0;
Change(v, 0, INF);
return answer();
}
int dog(int v)
{
v--;
x[v] = 1;
Change(v, INF, 0);
return answer();
}
int neighbor(int v)
{
v--;
if (x[v] == 0) Change(v, 0, -INF);
if (x[v] == 1) Change(v, -INF, 0);
x[v] = -1;
return answer();
}