#include <algorithm>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#ifdef DEBUG
#include <time.h>
#endif
#define all(a) (a).begin(), (a).end()
#define rev(a) (a).rbegin(), (a).rend()
#define F first
#define S second
int recur_depth = 0;
#ifdef DEBUG
#define dbg(x) \
{ \
++recur_depth; \
auto x_ = x; \
--recur_depth; \
cerr << string(recur_depth, '\t') << "\e[91m" << __func__ << ":" \
<< __LINE__ << "\t" << #x << " = " << x_ << "\e[39m" << endl; \
}
#else
#define dbg(x)
#endif
using namespace std;
using namespace __gnu_pbds;
typedef pair<int, int> ii;
typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> llll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vii;
typedef vector<vii> vvii;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pair<ll, ll>> vll;
typedef vector<vll> vvll;
typedef vector<bool> vb;
template <class type1>
using ordered_set = tree<type1, null_type, less<type1>, rb_tree_tag,
tree_order_statistics_node_update>;
template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p) {
return os << '(' << p.first << ", " << p.second << ')';
}
template <typename T_container, typename T = typename enable_if<
!is_same<T_container, string>::value,
typename T_container::value_type>::type>
ostream &operator<<(ostream &os, const T_container &v) {
os << '{';
string sep;
for (const T &x : v)
os << sep << x, sep = ", ";
return os << '}';
}
const ll MOD = 1e9 + 7;
// const ll MOD = 998244353;
const ll INF = 1e9;
const ld EPS = 1e-9;
struct ST {
const int MAXLG = 22;
int n;
vi lg2;
vvii st;
ST(vii &a) : n(a.size()) {
st = vvii(MAXLG, vii(n));
st[0] = a;
for (int j = 1; j < MAXLG; j++)
for (int i = 0; i + (1 << j) <= n; i++)
st[j][i] = min(st[j - 1][i], st[j - 1][i + (1 << (j - 1))]);
lg2 = vi(n + 1);
lg2[1] = 0;
for (int i = 2; i <= n; i++)
lg2[i] = lg2[i / 2] + 1;
}
int query(int l, int r) {
if (l > r)
swap(l, r);
int k = lg2[r - l + 1];
return min(st[k][l], st[k][r - (1 << k) + 1]).second;
}
};
void solve() {
int n, k;
cin >> n >> k;
vvi adj(n);
for (int i = 0; i < n - 1; i++) {
int u, v;
cin >> u >> v;
u--, v--;
adj[u].push_back(v);
adj[v].push_back(u);
}
vi st(n);
for (int &x : st)
cin >> x, x--;
int timer = 0;
vi par(n, -1), depth(n), first_occ(n, -1), tin(n), tout(n);
vii euler;
function<void(int, int)> f = [&](int u, int p) {
tin[u] = timer++;
first_occ[u] = euler.size();
euler.push_back({depth[u], u});
for (int &v : adj[u])
if (v != p) {
par[v] = u;
depth[v] = depth[u] + 1;
f(v, u);
euler.push_back({depth[u], u});
}
tout[u] = timer++;
};
f(0, -1);
ST lc(euler);
vvi by_state(k);
for (int i = 0; i < n; i++)
by_state[st[i]].push_back(i);
for (int i = 0; i < k; i++)
sort(all(by_state[i]),
[&](int u, int v) { return first_occ[u] < first_occ[v]; });
vb bad(n, 1);
auto mark = [&](int u, int p) {
assert(tin[p] <= tin[u] && tout[u] <= tout[p]);
while (u != p)
bad[u] = 0, u = par[u];
};
for (int state = 0; state < k; state++) {
if (by_state[state].size() <= 1)
continue;
int lca =
lc.query(first_occ[by_state[state][0]], first_occ[by_state[state][1]]);
mark(by_state[state][0], lca);
mark(by_state[state][1], lca);
for (int i = 2; i < by_state[state].size(); i++) {
int v = by_state[state][i];
int tmp = lc.query(first_occ[by_state[state][i - 1]], first_occ[v]);
mark(v, tmp);
lca = lc.query(lca, v);
}
}
vb vis(n);
vi comp(n);
function<void(int, int, int)> g = [&](int u, int p, int cc_id) {
comp[u] = cc_id;
vis[u] = 1;
for (int &v : adj[u])
if (v != p)
if ((u == par[v] && !bad[v]) || (v == par[u] && !bad[u])) {
g(v, u, cc_id);
}
};
int cc_id = 0;
for (int i = 0; i < n; i++)
if (!vis[i])
g(i, -1, cc_id++);
int nn = cc_id;
vector<set<int>> nadj(nn);
for (int i = 0; i < n; i++)
for (int j : adj[i])
if (comp[i] != comp[j])
nadj[comp[i]].insert(comp[j]), nadj[comp[j]].insert(comp[i]);
int no_leaves = 0;
for (int i = 1; i < nn; i++)
if (nadj[i].size() == 1)
no_leaves++;
cout << (no_leaves + 1) / 2 << "\n";
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(NULL);
clock_t start = clock();
int test_cases = 1;
// cin >> test_cases;
while (test_cases--)
solve();
#ifdef DEBUG
cerr << fixed << setprecision(10)
<< "\nTime Taken: " << (double)(clock() - start) / CLOCKS_PER_SEC
<< "s\n";
#endif
return 0;
}
Compilation message
mergers.cpp: In function 'void solve()':
mergers.cpp:176:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
176 | for (int i = 2; i < by_state[state].size(); i++) {
| ~~^~~~~~~~~~~~~~~~~~~~~~~~
mergers.cpp: In function 'int main()':
mergers.cpp:221:11: warning: unused variable 'start' [-Wunused-variable]
221 | clock_t start = clock();
| ^~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
324 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
212 KB |
Output is correct |
5 |
Correct |
0 ms |
212 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
316 KB |
Output is correct |
11 |
Correct |
0 ms |
340 KB |
Output is correct |
12 |
Correct |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
316 KB |
Output is correct |
14 |
Correct |
1 ms |
360 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
324 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
212 KB |
Output is correct |
5 |
Correct |
0 ms |
212 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
316 KB |
Output is correct |
11 |
Correct |
0 ms |
340 KB |
Output is correct |
12 |
Correct |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
316 KB |
Output is correct |
14 |
Correct |
1 ms |
360 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
324 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
212 KB |
Output is correct |
5 |
Correct |
0 ms |
212 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
316 KB |
Output is correct |
11 |
Correct |
0 ms |
340 KB |
Output is correct |
12 |
Correct |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
316 KB |
Output is correct |
14 |
Correct |
1 ms |
360 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
66 ms |
47776 KB |
Output is correct |
2 |
Incorrect |
145 ms |
66976 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
324 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
212 KB |
Output is correct |
5 |
Correct |
0 ms |
212 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
340 KB |
Output is correct |
9 |
Correct |
1 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
316 KB |
Output is correct |
11 |
Correct |
0 ms |
340 KB |
Output is correct |
12 |
Correct |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
316 KB |
Output is correct |
14 |
Correct |
1 ms |
360 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |