Problem p02698 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pii pair<int, int>
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep3(i, l, n) for (int i = l; i < (n); ++i)
#define sz(v) (int)v.size()
#define endl '\\n'
const int inf = 1000000007;
const ll INF = 1e18;
// int mod = 998244353;
int mod = 1000000007;
#define abs(x) (x >= 0 ? x : -(x))
#define lb(v, x) (int)(lower_bound(all(v), x) - v.begin())
#define ub(v, x) (int)(upper_bound(all(v), x) - v.begin())
template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
ll gcd(ll a, ll b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
template <typename T1, typename T2> T1 pow_(T1 a, T2 b) {
  return b ? pow_(a * a, b / 2) * (b % 2 ? a : 1) : 1;
}
ll modpow(ll a, ll b, ll _mod) {
  return b ? modpow(a * a % _mod, b / 2, _mod) * (b % 2 ? a : 1) % _mod : 1;
}
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  os << p.F << " " << p.S;
  return os;
}
template <class T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  rep(i, sz(vec)) {
    if (i)
      os << " ";
    os << vec[i];
  }
  return os;
}
template <typename T> inline istream &operator>>(istream &is, vector<T> &v) {
  rep(j, sz(v)) is >> v[j];
  return is;
}
template <class T, class T2> inline void add(T &a, T2 b) {
  a += b;
  if (a >= mod)
    a -= mod;
}

void solve();

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cout << fixed << setprecision(10);
  int T;
  T = 1;
  while (T--)
    solve();
}

vector<int> a;
vector<vector<int>> G;
vector<int> ans;
vector<int> lis;

void dfs(int v, int p) {
  for (int nv : G[v]) {
    if (nv == p)
      continue;
    int it = lb(lis, a[nv]);
    int i = -1, j = -1;
    if (it == sz(lis)) {
      lis.eb(a[nv]);
      i = sz(lis);
    } else {
      i = it;
      j = lis[it];
      lis[it] = a[nv];
    }
    // cout << v << " " << nv << "  " << lis << endl;
    dfs(nv, v);
    ans[nv] = sz(lis);
    if (i == sz(lis)) {
      lis.pop_back();
    } else {
      lis[i] = j;
    }
  }
}

void solve() {
  int n;
  cin >> n;
  a.resize(n);
  cin >> a;
  G.resize(n);
  ans.resize(n);
  rep(i, n - 1) {
    int a, b;
    cin >> a >> b;
    a--;
    b--;
    G[a].eb(b);
    G[b].eb(a);
  }
  lis.eb(a[0]);
  dfs(0, -1);
  ans[0] = 1;
  rep(i, n) cout << ans[i] << endl;
}


Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pii pair<int, int>
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep3(i, l, n) for (int i = l; i < (n); ++i)
#define sz(v) (int)v.size()
#define endl '\\n'
const int inf = 1000000007;
const ll INF = 1e18;
// int mod = 998244353;
int mod = 1000000007;
#define abs(x) (x >= 0 ? x : -(x))
#define lb(v, x) (int)(lower_bound(all(v), x) - v.begin())
#define ub(v, x) (int)(upper_bound(all(v), x) - v.begin())
template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
ll gcd(ll a, ll b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
template <typename T1, typename T2> T1 pow_(T1 a, T2 b) {
  return b ? pow_(a * a, b / 2) * (b % 2 ? a : 1) : 1;
}
ll modpow(ll a, ll b, ll _mod) {
  return b ? modpow(a * a % _mod, b / 2, _mod) * (b % 2 ? a : 1) % _mod : 1;
}
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  os << p.F << " " << p.S;
  return os;
}
template <class T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  rep(i, sz(vec)) {
    if (i)
      os << " ";
    os << vec[i];
  }
  return os;
}
template <typename T> inline istream &operator>>(istream &is, vector<T> &v) {
  rep(j, sz(v)) is >> v[j];
  return is;
}
template <class T, class T2> inline void add(T &a, T2 b) {
  a += b;
  if (a >= mod)
    a -= mod;
}

void solve();

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cout << fixed << setprecision(10);
  int T;
  T = 1;
  while (T--)
    solve();
}

vector<int> a;
vector<vector<int>> G;
vector<int> ans;
vector<int> x;

void dfs(int v, int p) {
  if (p != -1 && sz(G[v]) == 1) {
    vector<int> lis;
    lis.eb(a[0]);
    // cout << x << endl;
    rep(i, sz(x)) {
      int it = lb(lis, a[x[i]]);
      if (it == sz(lis)) {
        lis.eb(a[x[i]]);
      } else {
        lis[it] = a[x[i]];
      }
      chmax(ans[x[i]], sz(lis));
    }
    return;
  }
  for (int nv : G[v]) {
    if (nv == p)
      continue;
    x.eb(nv);
    dfs(nv, v);
    x.pop_back();
  }
}
void solve() {
  int n;
  cin >> n;
  a.resize(n);
  cin >> a;
  G.resize(n);
  ans.resize(n);
  rep(i, n - 1) {
    int a, b;
    cin >> a >> b;
    a--;
    b--;
    G[a].eb(b);
    G[b].eb(a);
  }
  dfs(0, -1);
  cout << 1 << endl;
  rep3(i, 1, n) cout << ans[i] << endl;
}