Synchronization
Método 1 - ?
Al borrar una arista, recordamos con cuántos sistemas se usó esa arista para sincronizar. Además, en cada momento en que hay una componente conexa, todas las computadoras de la componente tienen el mismo valor.
^ Esto es creo
Si usamos HLD o LCT entonces es .
Método 2 - Descomposición por centroide
¡Parece que es muy rápido!
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using db = double;
using str = string; // yay python!
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<db, db>;
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>;
using vs = vector<str>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vpd = vector<pd>;
#define tcT template <class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT > using V = vector<T>;
tcT, size_t SZ > using AR = array<T, SZ>;
tcT > using PR = pair<T, T>;
// pairs
#define mp make_pair
#define f first
#define s second
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pb push_back
#define eb emplace_back
#define pf push_front
#define lb lower_bound
#define ub upper_bound
tcT > int lwb(V<T> &a, const T &b) { return int(lb(all(a), b) - bg(a)); }
// loops
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define trav(a, x) for (auto &a : x)
const int MOD = 1e9 + 7; // 998244353;
const int MX = 2e5 + 5;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
template <class T> using pqg = priority_queue<T, vector<T>, greater<T>>;
// bitwise ops
// also see https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html
constexpr int pct(int x) { return __builtin_popcount(x); } // # of bits set
constexpr int bits(int x) { // assert(x >= 0); // make C++11 compatible until
// USACO updates ...
return x == 0 ? 0 : 31 - __builtin_clz(x);
} // floor(log2(x))
constexpr int p2(int x) { return 1 << x; }
constexpr int msk2(int x) { return p2(x) - 1; }
ll cdiv(ll a, ll b) {
return a / b + ((a ^ b) > 0 && a % b);
} // divide a by b rounded up
ll fdiv(ll a, ll b) {
return a / b - ((a ^ b) < 0 && a % b);
} // divide a by b rounded down
tcT > bool ckmin(T &a, const T &b) { return b < a ? a = b, 1 : 0; } // set a = min(a,b)
tcT > bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }
tcTU > T fstTrue(T lo, T hi, U f) {
hi++;
assert(lo <= hi); // assuming f is increasing
while (lo < hi) { // find first index such that f is true
T mid = lo + (hi - lo) / 2;
f(mid) ? hi = mid : lo = mid + 1;
}
return lo;
}
tcTU > T lstTrue(T lo, T hi, U f) {
lo--;
assert(lo <= hi); // assuming f is decreasing
while (lo < hi) { // find first index such that f is true
T mid = lo + (hi - lo + 1) / 2;
f(mid) ? lo = mid : hi = mid - 1;
}
return lo;
}
tcT > void remDup(vector<T> &v) { // sort and remove duplicates
sort(all(v));
v.erase(unique(all(v)), end(v));
}
tcTU > void erase(T &t, const U &u) { // don't erase
auto it = t.find(u);
assert(it != end(t));
t.erase(it);
} // element that doesn't exist from (multi)set
// INPUT
#define tcTUU tcT, class... U
tcT > void re(complex<T> &c);
tcTU > void re(pair<T, U> &p);
tcT > void re(V<T> &v);
tcT, size_t SZ > void re(AR<T, SZ> &a);
tcT > void re(T &x) { cin >> x; }
void re(db &d) {
str t;
re(t);
d = stod(t);
}
void re(ld &d) {
str t;
re(t);
d = stold(t);
}
tcTUU > void re(T &t, U &...u) {
re(t);
re(u...);
}
tcT > void re(complex<T> &c) {
T a, b;
re(a, b);
c = {a, b};
}
tcTU > void re(pair<T, U> &p) { re(p.f, p.s); }
tcT > void re(V<T> &x) { trav(a, x) re(a); }
tcT, size_t SZ > void re(AR<T, SZ> &x) { trav(a, x) re(a); }
tcT > void rv(int n, V<T> &x) {
x.rsz(n);
re(x);
}
// TO_STRING
#define ts to_string
str ts(char c) { return str(1, c); }
str ts(const char *s) { return (str)s; }
str ts(str s) { return s; }
str ts(bool b) {
#ifdef LOCAL
return b ? "true" : "false";
#else
return ts((int)b);
#endif
}
tcT > str ts(complex<T> c) {
stringstream ss;
ss << c;
return ss.str();
}
str ts(V<bool> v) {
str res = "{";
F0R(i, sz(v)) res += char('0' + v[i]);
res += "}";
return res;
}
template <size_t SZ> str ts(bitset<SZ> b) {
str res = "";
F0R(i, SZ) res += char('0' + b[i]);
return res;
}
tcTU > str ts(pair<T, U> p);
tcT > str ts(T v) { // containers with begin(), end()
#ifdef LOCAL
bool fst = 1;
str res = "{";
for (const auto &x : v) {
if (!fst) res += ", ";
fst = 0;
res += ts(x);
}
res += "}";
return res;
#else
bool fst = 1;
str res = "";
for (const auto &x : v) {
if (!fst) res += " ";
fst = 0;
res += ts(x);
}
return res;
#endif
}
tcTU > str ts(pair<T, U> p) {
#ifdef LOCAL
return "(" + ts(p.f) + ", " + ts(p.s) + ")";
#else
return ts(p.f) + " " + ts(p.s);
#endif
}
// OUTPUT
tcT > void pr(T x) { cout << ts(x); }
tcTUU > void pr(const T &t, const U &...u) {
pr(t);
pr(u...);
}
void ps() { pr("\n"); } // print w/ spaces
tcTUU > void ps(const T &t, const U &...u) {
pr(t);
if (sizeof...(u)) pr(" ");
ps(u...);
}
// DEBUG
void DBG() { cerr << "]" << endl; }
tcTUU > void DBG(const T &t, const U &...u) {
cerr << ts(t);
if (sizeof...(u)) cerr << ", ";
DBG(u...);
}
#ifdef LOCAL // compile with -DLOCAL, chk -> fake assert
#define dbg(...) \
cerr << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#define chk(...) \
if (!(__VA_ARGS__)) \
cerr << "Line(" << __LINE__ << ") -> function(" << __FUNCTION__ \
<< ") -> CHK FAILED: (" << #__VA_ARGS__ << ")" << "\n", \
exit(0);
#else
#define dbg(...) 0
#define chk(...) 0
#endif
void setPrec() { cout << fixed << setprecision(15); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
// FILE I/O
void setIn(str s) { freopen(s.c_str(), "r", stdin); }
void setOut(str s) { freopen(s.c_str(), "w", stdout); }
void setIO(str s = "") {
unsyncIO();
setPrec();
// cin.exceptions(cin.failbit);
// throws exception when do smth illegal
// ex. try to read letter into int
if (sz(s)) setIn(s + ".in"), setOut(s + ".out"); // for USACO
}
vpi adj[MX];
int N, M, Q, ans[MX];
vi change[MX];
vpi bad[MX];
bool done[MX]; // processed as centroid yet
int sub[MX], cen[MX]; // subtree size, centroid anc
map<int, list<int>> to[MX], from[MX];
void dfs(int x, int p) {
sub[x] = 1;
trav(y, adj[x]) if (!done[y.f] && y.f != p) dfs(y.f, x), sub[x] += sub[y.f];
}
int centroid(int x) {
dfs(x, -1);
for (int sz = sub[x];;) {
pi mx = {0, 0};
trav(y, adj[x]) if (!done[y.f] && sub[y.f] < sub[x]) ckmax(mx, {sub[y.f], y.f});
if (mx.f * 2 <= sz) return x;
x = mx.s;
}
}
void ad(list<int> &a, list<int> &b) {
a.splice(end(a), b);
assert(!sz(b));
}
void merge(map<int, list<int>> &a, map<int, list<int>> &b) {
if (sz(a) < sz(b)) swap(a, b);
trav(t, b) ad(a[t.f], t.s);
b.clear();
}
void getAll(list<int> &x, map<int, list<int>> &a, pi p) {
while (1) {
auto it = a.ub(p.f);
if (it == end(a) || it->f >= p.s) break;
ad(x, it->s);
a.erase(it);
}
}
void oops(int a, int b) {
trav(t, adj[a]) if (!done[t.f] && t.f != b) {
oops(t.f, a);
trav(z, bad[t.s]) {
{
list<int> x;
getAll(x, to[t.f], z);
if (sz(x)) ad(to[t.f][z.f], x);
}
{
list<int> x;
getAll(x, from[t.f], z);
if (sz(x)) ad(from[t.f][z.s], x);
}
}
merge(to[a], to[t.f]), merge(from[a], from[t.f]);
}
to[a][M + 1].pb(a);
from[a][0].pb(a);
}
int comp[MX];
void makeLabel(int a, int b, int cnt) {
comp[a] = cnt;
trav(t, adj[a]) if (!done[t.f] && t.f != b) makeLabel(t.f, a, cnt);
}
int genLabel(int x) {
comp[x] = 0;
int cnt = 1;
trav(y, adj[x]) if (!done[y.f]) { makeLabel(y.f, x, cnt++); }
return cnt;
}
void gen(int CEN, int _x) { // CEN = centroid above x
int x = centroid(_x);
done[x] = 1;
cen[x] = CEN;
sub[x] = sub[_x];
int num = genLabel(x);
oops(x, -1);
vi cnt(num);
vector<pair<int, list<int>>> TO(all(to[x]));
vector<pair<int, list<int>>> FROM(all(from[x]));
int ind = 0, sum = 0;
trav(t, TO) {
while (ind < sz(FROM) && FROM[ind].f <= t.f) {
trav(u, FROM[ind].s) cnt[comp[u]]++, sum++;
ind++;
}
trav(u, t.s) {
ans[u] += sum;
if (comp[u]) ans[u] -= cnt[comp[u]];
}
}
to[x].clear(), from[x].clear();
trav(y, adj[x]) if (!done[y.f]) gen(x, y.f);
}
void init(int _N) {
N = _N;
FOR(i, 1, N + 1) done[i] = 0;
gen(-1, 1);
} // start at vert 1
int main() {
setIO();
re(N, M, Q);
F0R(i, N - 1) {
int X, Y;
re(X, Y);
adj[X].pb({Y, i}), adj[Y].pb({X, i});
}
F0R(i, N - 1) change[i].pb(-5);
FOR(i, 1, M + 1) {
int D;
re(D);
D--;
change[D].pb(i);
}
F0R(i, N - 1) {
if (sz(change[i]) & 1) change[i].pb(M + 5);
for (int j = 0; j < sz(change[i]); j += 2)
bad[i].pb({change[i][j], change[i][j + 1]});
}
init(N);
F0R(i, Q) {
int c;
re(c);
ps(ans[c]);
}
}