#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define ll long long
#define mp(x, y) make_pair(x, y)
#define sz(v) ((int) (v).size())
#define all(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define BIT(x, y) (((x) >> (y)) & 1)
#define pb push_back
#define heap priority_queue
#define max_rng *max_element
#define min_rng *min_element
#define rep(i, n) for(int i = 1, _n = (n); i <= _n; ++i)
#define forn(i, a, b) for(int i = (a), _b = (b); i <= _b; ++i)
#define ford(i, a, b) for(int i = (a), _b = (b); i >= _b; --i)
template <class X, class Y>
inline bool maximize(X &x, Y y) {
return (x < y ? x = y, true : false);
}
template <class X, class Y>
inline bool minimize(X &x, Y y) {
return (x > y ? x = y, true : false);
}
template <class X>
inline void compress(vector<X> &a) {
sort(all(a));
a.resize(unique(all(a)) - a.begin());
}
int ctz(ll x) { return __builtin_ctzll(x); }
int lg(ll x) { return 63 - __builtin_clzll(x); }
int popcount(ll x) { return __builtin_popcount(x); }
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) {
return l + abs((ll) rng()) % (r - l + 1);
}
const ll oo = (ll) 1e17;
const int inf = (ll) 1e9 + 7, mod = (ll) 1e9 + 7;
const int N = 1e4 + 5, M = 5555;
void add(int &x, int y) { x += y; if (x >= mod) x -= mod; }
void sub(int &x, int y) { x -= y; if (x < 0) x += mod; }
int n, m;
int a[N];
vector<int> g[N];
vector<pair<int, int>> S[N];
void dfs(int u, int p) {
int val = a[u];
vector<pair<int, int>> left, right;
for (int v : g[u]) if (v != p) {
dfs(v, u);
for (pair<int, int> i : S[v]) {
if (i.second < val) left.pb(i);
else if (i.first > val) right.pb(i);
}
}
map<int, int> dpL, dpR;
dpL[val] = dpR[val] = 1;
sort(all(left)); reverse(all(left));
for(pair<int, int> i : left) {
dpL[i.first] += dpL[i.second + 1];
}
sort(all(right));
for (pair<int, int> i : right) {
dpR[i.second] += dpR[i.first - 1];
}
for (pair<int, int> i : dpL)
for (pair<int, int> j : dpR) {
if (i.second * j.second != 0)
S[u].pb(mp(i.first, j.first));
}
compress(S[u]);
}
signed main(void) {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n;
rep(i, n) cin >> a[i];
rep(i, n - 1) {
int u, v;
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
dfs(1, 0);
cout << sz(S[1]);
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
860 KB |
Output is correct |
2 |
Correct |
1 ms |
936 KB |
Output is correct |
3 |
Correct |
1 ms |
860 KB |
Output is correct |
4 |
Correct |
1 ms |
860 KB |
Output is correct |
5 |
Correct |
0 ms |
860 KB |
Output is correct |
6 |
Correct |
1 ms |
860 KB |
Output is correct |
7 |
Correct |
1 ms |
860 KB |
Output is correct |
8 |
Correct |
1 ms |
856 KB |
Output is correct |
9 |
Correct |
0 ms |
860 KB |
Output is correct |
10 |
Correct |
1 ms |
920 KB |
Output is correct |
11 |
Correct |
6 ms |
1628 KB |
Output is correct |
12 |
Correct |
5 ms |
1628 KB |
Output is correct |
13 |
Correct |
5 ms |
1724 KB |
Output is correct |
14 |
Correct |
39 ms |
10184 KB |
Output is correct |
15 |
Correct |
43 ms |
10068 KB |
Output is correct |
16 |
Correct |
39 ms |
10072 KB |
Output is correct |
17 |
Correct |
6 ms |
1628 KB |
Output is correct |
18 |
Correct |
5 ms |
1628 KB |
Output is correct |
19 |
Correct |
10 ms |
4160 KB |
Output is correct |
20 |
Correct |
10 ms |
3928 KB |
Output is correct |