Problem p02599 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <algorithm>
#include <bitset>
#include <cassert>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>
using namespace std;

// #define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
constexpr ll mod = 998244353;
const ll INF = mod * mod;
typedef pair<int, int> P;
#define stop                                                                   \\
  char nyaa;                                                                   \\
  cin >> nyaa;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
#define all(v) (v).begin(), (v).end()
typedef pair<ll, ll> LP;
typedef long double ld;
typedef pair<ld, ld> LDP;
const ld eps = 1e-12;
const ld pi = acos(-1.0);

ll mod_pow(ll x, ll n, ll m) {
  ll res = 1;
  while (n) {
    if (n & 1)
      res = res * x % m;
    x = x * x % m;
    n >>= 1;
  }
  return res;
}
struct modint {
  ll n;
  modint() : n(0) { ; }
  modint(ll m) : n(m) {
    if (n >= mod)
      n %= mod;
    else if (n < 0)
      n = (n % mod + mod) % mod;
  }
  operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
modint operator+=(modint &a, modint b) {
  a.n += b.n;
  if (a.n >= mod)
    a.n -= mod;
  return a;
}
modint operator-=(modint &a, modint b) {
  a.n -= b.n;
  if (a.n < 0)
    a.n += mod;
  return a;
}
modint operator*=(modint &a, modint b) {
  a.n = ((ll)a.n * b.n) % mod;
  return a;
}
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, int n) {
  if (n == 0)
    return modint(1);
  modint res = (a * a) ^ (n / 2);
  if (n % 2)
    res = res * a;
  return res;
}

ll inv(ll a, ll p) { return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p); }
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }

const int max_n = 1 << 18;
modint fact[max_n], factinv[max_n];
void init_f() {
  fact[0] = modint(1);
  for (int i = 0; i < max_n - 1; i++) {
    fact[i + 1] = fact[i] * modint(i + 1);
  }
  factinv[max_n - 1] = modint(1) / fact[max_n - 1];
  for (int i = max_n - 2; i >= 0; i--) {
    factinv[i] = factinv[i + 1] * modint(i + 1);
  }
}
modint comb(int a, int b) {
  if (a < 0 || b < 0 || a < b)
    return 0;
  return fact[a] * factinv[b] * factinv[a - b];
}

struct BIT {
private:
  vector<ll> node;
  int n;

public:
  BIT(int n_) {
    n = n_;
    node.resize(n, 0);
  }
  // 0-indexed
  void add(int a, ll w) {
    for (int i = a; i < n; i |= i + 1)
      node[i] += w;
  }
  //[0,a)
  ll sum(int a) {
    ll ret = 0;
    for (int i = a - 1; i >= 0; i = (i & (i + 1)) - 1)
      ret += node[i];
    return ret;
  }
  //[a,b)
  ll sum(int a, int b) { return sum(b) - sum(a); }
};

void solve() {
  int n;
  cin >> n;
  int q;
  cin >> q;
  vector<int> c(n);
  rep(i, n) cin >> c[i];

  vector<int> las(n + 1, n);
  vector<int> ri(n);
  per(i, n) {
    ri[i] = las[c[i]];
    las[c[i]] = i;
  }
  BIT bt(n + 1);
  vector<bool> used(n + 1, false);
  rep(i, n) {
    if (!used[c[i]]) {
      bt.add(i, 1);
      used[c[i]] = true;
    }
  }
  vector<vector<P>> qs(n);
  rep(i, q) {
    int l, r;
    cin >> l >> r;
    l--;
    r--;
    qs[l].push_back({i, r});
  }
  vector<int> ans(q);
  rep(i, n) {
    for (P p : qs[i]) {
      int r = p.second;
      int id = p.first;
      ans[id] = bt.sum(r + 1);
    }
    bt.add(i, -1);
    bt.add(ri[i], 1);
  }
  rep(i, q) cout << ans[i] << "\\n";
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  // cout << fixed << setprecision(10);
  // init_f();
  // cout << grandy(2, 3, false, false) << "\\n";
  // int t; cin >> t; rep(i, t)
  solve();
  return 0;
}


Error: TLE

Fixed submission:

#include <algorithm>
#include <bitset>
#include <cassert>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>
using namespace std;

// #define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
constexpr ll mod = 998244353;
const ll INF = mod * mod;
typedef pair<int, int> P;
#define stop                                                                   \\
  char nyaa;                                                                   \\
  cin >> nyaa;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
#define all(v) (v).begin(), (v).end()
typedef pair<ll, ll> LP;
typedef long double ld;
typedef pair<ld, ld> LDP;
const ld eps = 1e-12;
const ld pi = acos(-1.0);

ll mod_pow(ll x, ll n, ll m) {
  ll res = 1;
  while (n) {
    if (n & 1)
      res = res * x % m;
    x = x * x % m;
    n >>= 1;
  }
  return res;
}
struct modint {
  ll n;
  modint() : n(0) { ; }
  modint(ll m) : n(m) {
    if (n >= mod)
      n %= mod;
    else if (n < 0)
      n = (n % mod + mod) % mod;
  }
  operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
modint operator+=(modint &a, modint b) {
  a.n += b.n;
  if (a.n >= mod)
    a.n -= mod;
  return a;
}
modint operator-=(modint &a, modint b) {
  a.n -= b.n;
  if (a.n < 0)
    a.n += mod;
  return a;
}
modint operator*=(modint &a, modint b) {
  a.n = ((ll)a.n * b.n) % mod;
  return a;
}
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, int n) {
  if (n == 0)
    return modint(1);
  modint res = (a * a) ^ (n / 2);
  if (n % 2)
    res = res * a;
  return res;
}

ll inv(ll a, ll p) { return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p); }
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }

const int max_n = 1 << 18;
modint fact[max_n], factinv[max_n];
void init_f() {
  fact[0] = modint(1);
  for (int i = 0; i < max_n - 1; i++) {
    fact[i + 1] = fact[i] * modint(i + 1);
  }
  factinv[max_n - 1] = modint(1) / fact[max_n - 1];
  for (int i = max_n - 2; i >= 0; i--) {
    factinv[i] = factinv[i + 1] * modint(i + 1);
  }
}
modint comb(int a, int b) {
  if (a < 0 || b < 0 || a < b)
    return 0;
  return fact[a] * factinv[b] * factinv[a - b];
}

struct range_tree {
private:
  int sz = 1;
  vector<vector<int>> node;
  vector<vector<int>> lh, rh;

public:
  range_tree(vector<int> v) {
    int n = v.size();
    while (sz < n)
      sz *= 2;
    node.resize(sz * 2 - 1);
    rep(i, n) { node[i + sz - 1].push_back(v[i]); }
    lh.resize(2 * sz - 1), rh.resize(2 * sz - 1);
    per(i, sz - 1) {
      int id1 = 0, id2 = 0;
      vector<int> &a = node[2 * i + 1];
      vector<int> &b = node[2 * i + 2];
      while (id1 < a.size() || id2 < b.size()) {
        int mi = mod;
        if (id1 < a.size())
          mi = min(mi, a[id1]);
        if (id2 < b.size())
          mi = min(mi, b[id2]);
        int m1 = id1, m2 = id2;
        while (id1 < a.size() && mi == a[id1]) {
          node[i].push_back(a[id1]);
          id1++;
          lh[i].push_back(m1);
          rh[i].push_back(m2);
        }
        while (id2 < b.size() && mi == b[id2]) {
          node[i].push_back(b[id2]);
          id2++;
          lh[i].push_back(m1);
          rh[i].push_back(m2);
        }
      }
      lh[i].push_back(a.size());
      rh[i].push_back(b.size());
    }
  }
  struct tquery {
    int loc, k, l, r;
  };
  ll query(ll x, int a, int b) {
    int loc = lower_bound(all(node[0]), x) - node[0].begin();
    vector<tquery> st;
    st.push_back({loc, 0, 0, sz});
    ll res = 0;
    while (!st.empty()) {
      tquery tq = st.back();
      st.pop_back();
      if (tq.r <= a || b <= tq.l)
        continue;
      if (a <= tq.l && tq.r <= b) {
        res += tq.loc;
      } else {
        st.push_back({lh[tq.k][tq.loc], 2 * tq.k + 1, tq.l, (tq.l + tq.r) / 2});
        st.push_back({rh[tq.k][tq.loc], 2 * tq.k + 2, (tq.l + tq.r) / 2, tq.r});
      }
    }
    return res;
  }
};

void solve() {
  int n;
  cin >> n;
  int q;
  cin >> q;
  vector<int> c(n);
  rep(i, n) cin >> c[i];

  vector<int> las(n + 1, n);
  vector<int> ri(n);
  per(i, n) {
    ri[i] = las[c[i]];
    las[c[i]] = i;
  }
  range_tree rt(ri);
  rep(i, q) {
    int l, r;
    cin >> l >> r;
    l--;
    r--;
    int ans = r - l + 1;
    ans -= rt.query(r + 1, l, r + 1);
    cout << ans << "\\n";
  }
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  // cout << fixed << setprecision(10);
  // init_f();
  // cout << grandy(2, 3, false, false) << "\\n";
  // int t; cin >> t; rep(i, t)
  solve();
  return 0;
}