Problem p02538 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define lscan(x) scanf("%I64d", &x)
#define lprint(x) printf("%I64d", x)
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define rep2(i, n) for (ll i = n - 1; i >= 0; i--)
const int mod = 998244353;

ll gcd(ll a, ll b) {
  ll c = a % b;
  while (c != 0) {
    a = b;
    b = c;
    c = a % b;
  }
  return b;
}

long long extGCD(long long a, long long b, long long &x, long long &y) {
  if (b == 0) {
    x = 1;
    y = 0;
    return a;
  }
  long long d = extGCD(b, a % b, y, x);
  y -= a / b * x;
  return d;
}

struct UnionFind {
  vector<ll> data;

  UnionFind(int sz) { data.assign(sz, -1); }

  bool unite(int x, int y) {
    x = find(x), y = find(y);
    if (x == y)
      return (false);
    if (data[x] > data[y])
      swap(x, y);
    data[x] += data[y];
    data[y] = x;
    return (true);
  }

  int find(int k) {
    if (data[k] < 0)
      return (k);
    return (data[k] = find(data[k]));
  }

  ll size(int k) { return (-data[find(k)]); }
};

ll M = 1000000007;

vector<ll> fac(2000011);  // n!(mod M)
vector<ll> ifac(2000011); // k!^{M-2} (mod M)

ll mpow(ll x, ll n) {
  ll ans = 1;
  while (n != 0) {
    if (n & 1)
      ans = ans * x % M;
    x = x * x % M;
    n = n >> 1;
  }
  return ans;
}
ll mpow2(ll x, ll n, ll mod) {
  ll ans = 1;
  while (n != 0) {
    if (n & 1)
      ans = ans * x % mod;
    x = x * x % mod;
    n = n >> 1;
  }
  return ans;
}
void setcomb() {
  fac[0] = 1;
  ifac[0] = 1;
  for (ll i = 0; i < 2000010; i++) {
    fac[i + 1] = fac[i] * (i + 1) % M; // n!(mod M)
  }
  ifac[2000010] = mpow(fac[2000010], M - 2);
  for (ll i = 2000010; i > 0; i--) {
    ifac[i - 1] = ifac[i] * i % M;
  }
}
ll comb(ll a, ll b) {
  if (a == 0 && b == 0)
    return 1;
  if (a < b || a < 0)
    return 0;
  ll tmp = ifac[a - b] * ifac[b] % M;
  return tmp * fac[a] % M;
}
ll perm(ll a, ll b) {
  if (a == 0 && b == 0)
    return 1;
  if (a < b || a < 0)
    return 0;
  return fac[a] * ifac[a - b] % M;
}
long long modinv(long long a) {
  long long b = M, u = 1, v = 0;
  while (b) {
    long long t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= M;
  if (u < 0)
    u += M;
  return u;
}
ll modinv2(ll a, ll mod) {
  ll b = mod, u = 1, v = 0;
  while (b) {
    ll t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= mod;
  if (u < 0)
    u += mod;
  return u;
}

template <int mod> struct ModInt {
  int x;

  ModInt() : x(0) {}

  ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}

  ModInt &operator+=(const ModInt &p) {
    if ((x += p.x) >= mod)
      x -= mod;
    return *this;
  }

  ModInt &operator-=(const ModInt &p) {
    if ((x += mod - p.x) >= mod)
      x -= mod;
    return *this;
  }

  ModInt &operator*=(const ModInt &p) {
    x = (int)(1LL * x * p.x % mod);
    return *this;
  }

  ModInt &operator/=(const ModInt &p) {
    *this *= p.inverse();
    return *this;
  }

  ModInt operator-() const { return ModInt(-x); }

  ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }

  ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }

  ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }

  ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }

  bool operator==(const ModInt &p) const { return x == p.x; }

  bool operator!=(const ModInt &p) const { return x != p.x; }

  ModInt inverse() const {
    int a = x, b = mod, u = 1, v = 0, t;
    while (b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    return ModInt(u);
  }

  ModInt pow(int64_t n) const {
    ModInt ret(1), mul(x);
    while (n > 0) {
      if (n & 1)
        ret *= mul;
      mul *= mul;
      n >>= 1;
    }
    return ret;
  }

  friend ostream &operator<<(ostream &os, const ModInt &p) { return os << p.x; }

  friend istream &operator>>(istream &is, ModInt &a) {
    int64_t t;
    is >> t;
    a = ModInt<mod>(t);
    return (is);
  }

  static int get_mod() { return mod; }
};

using mint = ModInt<mod>;

vector<vector<mint>> mul(vector<vector<mint>> a, vector<vector<mint>> b) {
  int i, j, k;
  mint t;
  int n = a.size(), m = b[0].size(), l = a[0].size();
  vector<vector<mint>> c(n, vector<mint>(m));
  for (i = 0; i < n; i++) {
    for (j = 0; j < m; j++) {
      t = 0;
      for (k = 0; k < l; k++)
        t += a[i][k] * b[k][j];
      c[i][j] = t;
    }
  }
  return c;
}

vector<vector<mint>> mat_pow(vector<vector<mint>> x, ll n) {
  ll k = x.size();
  vector<vector<mint>> ans(k, vector<mint>(k, 0));
  for (int i = 0; i < k; i++)
    ans[i][i] = 1;
  while (n != 0) {
    if (n & 1)
      ans = mul(ans, x);
    x = mul(x, x);
    n = n >> 1;
  }
  return ans;
}

template <typename Monoid, typename OperatorMonoid = Monoid>
struct LazySegmentTree {
  using F = function<Monoid(Monoid, Monoid)>;
  using G = function<Monoid(Monoid, OperatorMonoid)>;
  using H = function<OperatorMonoid(OperatorMonoid, OperatorMonoid)>;

  int sz, height;
  vector<Monoid> data;
  vector<OperatorMonoid> lazy;
  const F f;
  const G g;
  const H h;
  const Monoid M1;
  const OperatorMonoid OM0;

  LazySegmentTree(int n, const F f, const G g, const H h, const Monoid &M1,
                  const OperatorMonoid OM0)
      : f(f), g(g), h(h), M1(M1), OM0(OM0) {
    sz = 1;
    height = 0;
    while (sz < n)
      sz <<= 1, height++;
    data.assign(2 * sz, M1);
    lazy.assign(2 * sz, OM0);
  }

  void set(int k, const Monoid &x) { data[k + sz] = x; }

  void build() {
    for (int k = sz - 1; k > 0; k--) {
      data[k] = f(data[2 * k + 0], data[2 * k + 1]);
    }
  }

  inline void propagate(int k) {
    if (lazy[k] != OM0) {
      lazy[2 * k + 0] = h(lazy[2 * k + 0], lazy[k]);
      lazy[2 * k + 1] = h(lazy[2 * k + 1], lazy[k]);
      data[k] = reflect(k);
      lazy[k] = OM0;
    }
  }

  inline Monoid reflect(int k) {
    return lazy[k] == OM0 ? data[k] : g(data[k], lazy[k]);
  }

  inline void recalc(int k) {
    while (k >>= 1)
      data[k] = f(reflect(2 * k + 0), reflect(2 * k + 1));
  }

  inline void thrust(int k) {
    for (int i = height; i > 0; i--)
      propagate(k >> i);
  }

  void update(int a, int b, const OperatorMonoid &x) {
    thrust(a += sz);
    thrust(b += sz - 1);
    for (int l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {
      if (l & 1)
        lazy[l] = h(lazy[l], x), ++l;
      if (r & 1)
        --r, lazy[r] = h(lazy[r], x);
    }
    recalc(a);
    recalc(b);
  }

  Monoid query(int a, int b) {
    thrust(a += sz);
    thrust(b += sz - 1);
    Monoid L = M1, R = M1;
    for (int l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {
      if (l & 1)
        L = f(L, reflect(l++));
      if (r & 1)
        R = f(reflect(--r), R);
    }
    return f(L, R);
  }

  Monoid operator[](const int &k) { return query(k, k + 1); }

  template <typename C>
  int find_subtree(int a, const C &check, Monoid &M, bool type) {
    while (a < sz) {
      propagate(a);
      Monoid nxt =
          type ? f(reflect(2 * a + type), M) : f(M, reflect(2 * a + type));
      if (check(nxt))
        a = 2 * a + type;
      else
        M = nxt, a = 2 * a + 1 - type;
    }
    return a - sz;
  }

  template <typename C> int find_first(int a, const C &check) {
    Monoid L = M1;
    if (a <= 0) {
      if (check(f(L, reflect(1))))
        return find_subtree(1, check, L, false);
      return -1;
    }
    thrust(a + sz);
    int b = sz;
    for (a += sz, b += sz; a < b; a >>= 1, b >>= 1) {
      if (a & 1) {
        Monoid nxt = f(L, reflect(a));
        if (check(nxt))
          return find_subtree(a, check, L, false);
        L = nxt;
        ++a;
      }
    }
    return -1;
  }

  template <typename C> int find_last(int b, const C &check) {
    Monoid R = M1;
    if (b >= sz) {
      if (check(f(reflect(1), R)))
        return find_subtree(1, check, R, true);
      return -1;
    }
    thrust(b + sz - 1);
    int a = sz;
    for (b += sz; a < b; a >>= 1, b >>= 1) {
      if (b & 1) {
        Monoid nxt = f(reflect(--b), R);
        if (check(nxt))
          return find_subtree(b, check, R, true);
        R = nxt;
      }
    }
    return -1;
  }
};

ll t[222222];
int main() {
  M = 998244353;
  ll n, q;
  cin >> n >> q;
  t[0] = 1;
  rep(i, n) t[i + 1] = t[i] * 10 % M;
  function<pair<mint, ll>(pair<mint, ll>, pair<mint, ll>)> f =
      [](pair<mint, ll> a, pair<mint, ll> b) {
        return mp(a.first * t[b.second] + b.first, a.second + b.second);
      };
  function<pair<mint, ll>(pair<mint, ll>, mint)> g = [](pair<mint, ll> a,
                                                        mint x) {
    if (x != 0)
      return mp(x * (t[a.second] - 1) / 9, a.second);
    else
      return a;
  };
  function<mint(mint, mint)> h = [](mint a, mint b) {
    if (b != 0)
      return b;
    else
      return a;
  };
  LazySegmentTree<pair<mint, ll>, mint> seg(n, f, g, h, mp(0, 0), 0);
  rep(i, n) seg.set(i, mp(1, 1));
  seg.build();
  rep(i, q) {
    ll l, r, d;
    cin >> l >> r >> d;
    seg.update(--l, r, d);
    cout << seg.query(0, n).first << endl;
  }
}


Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define lscan(x) scanf("%I64d", &x)
#define lprint(x) printf("%I64d", x)
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define rep2(i, n) for (ll i = n - 1; i >= 0; i--)
const int mod = 998244353;

ll gcd(ll a, ll b) {
  ll c = a % b;
  while (c != 0) {
    a = b;
    b = c;
    c = a % b;
  }
  return b;
}

long long extGCD(long long a, long long b, long long &x, long long &y) {
  if (b == 0) {
    x = 1;
    y = 0;
    return a;
  }
  long long d = extGCD(b, a % b, y, x);
  y -= a / b * x;
  return d;
}

struct UnionFind {
  vector<ll> data;

  UnionFind(int sz) { data.assign(sz, -1); }

  bool unite(int x, int y) {
    x = find(x), y = find(y);
    if (x == y)
      return (false);
    if (data[x] > data[y])
      swap(x, y);
    data[x] += data[y];
    data[y] = x;
    return (true);
  }

  int find(int k) {
    if (data[k] < 0)
      return (k);
    return (data[k] = find(data[k]));
  }

  ll size(int k) { return (-data[find(k)]); }
};

ll M = 1000000007;

vector<ll> fac(2000011);  // n!(mod M)
vector<ll> ifac(2000011); // k!^{M-2} (mod M)

ll mpow(ll x, ll n) {
  ll ans = 1;
  while (n != 0) {
    if (n & 1)
      ans = ans * x % M;
    x = x * x % M;
    n = n >> 1;
  }
  return ans;
}
ll mpow2(ll x, ll n, ll mod) {
  ll ans = 1;
  while (n != 0) {
    if (n & 1)
      ans = ans * x % mod;
    x = x * x % mod;
    n = n >> 1;
  }
  return ans;
}
void setcomb() {
  fac[0] = 1;
  ifac[0] = 1;
  for (ll i = 0; i < 2000010; i++) {
    fac[i + 1] = fac[i] * (i + 1) % M; // n!(mod M)
  }
  ifac[2000010] = mpow(fac[2000010], M - 2);
  for (ll i = 2000010; i > 0; i--) {
    ifac[i - 1] = ifac[i] * i % M;
  }
}
ll comb(ll a, ll b) {
  if (a == 0 && b == 0)
    return 1;
  if (a < b || a < 0)
    return 0;
  ll tmp = ifac[a - b] * ifac[b] % M;
  return tmp * fac[a] % M;
}
ll perm(ll a, ll b) {
  if (a == 0 && b == 0)
    return 1;
  if (a < b || a < 0)
    return 0;
  return fac[a] * ifac[a - b] % M;
}
long long modinv(long long a) {
  long long b = M, u = 1, v = 0;
  while (b) {
    long long t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= M;
  if (u < 0)
    u += M;
  return u;
}
ll modinv2(ll a, ll mod) {
  ll b = mod, u = 1, v = 0;
  while (b) {
    ll t = a / b;
    a -= t * b;
    swap(a, b);
    u -= t * v;
    swap(u, v);
  }
  u %= mod;
  if (u < 0)
    u += mod;
  return u;
}

template <int mod> struct ModInt {
  int x;

  ModInt() : x(0) {}

  ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}

  ModInt &operator+=(const ModInt &p) {
    if ((x += p.x) >= mod)
      x -= mod;
    return *this;
  }

  ModInt &operator-=(const ModInt &p) {
    if ((x += mod - p.x) >= mod)
      x -= mod;
    return *this;
  }

  ModInt &operator*=(const ModInt &p) {
    x = (int)(1LL * x * p.x % mod);
    return *this;
  }

  ModInt &operator/=(const ModInt &p) {
    *this *= p.inverse();
    return *this;
  }

  ModInt operator-() const { return ModInt(-x); }

  ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }

  ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }

  ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }

  ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }

  bool operator==(const ModInt &p) const { return x == p.x; }

  bool operator!=(const ModInt &p) const { return x != p.x; }

  ModInt inverse() const {
    int a = x, b = mod, u = 1, v = 0, t;
    while (b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    return ModInt(u);
  }

  ModInt pow(int64_t n) const {
    ModInt ret(1), mul(x);
    while (n > 0) {
      if (n & 1)
        ret *= mul;
      mul *= mul;
      n >>= 1;
    }
    return ret;
  }

  friend ostream &operator<<(ostream &os, const ModInt &p) { return os << p.x; }

  friend istream &operator>>(istream &is, ModInt &a) {
    int64_t t;
    is >> t;
    a = ModInt<mod>(t);
    return (is);
  }

  static int get_mod() { return mod; }
};

using mint = ModInt<mod>;

vector<vector<mint>> mul(vector<vector<mint>> a, vector<vector<mint>> b) {
  int i, j, k;
  mint t;
  int n = a.size(), m = b[0].size(), l = a[0].size();
  vector<vector<mint>> c(n, vector<mint>(m));
  for (i = 0; i < n; i++) {
    for (j = 0; j < m; j++) {
      t = 0;
      for (k = 0; k < l; k++)
        t += a[i][k] * b[k][j];
      c[i][j] = t;
    }
  }
  return c;
}

vector<vector<mint>> mat_pow(vector<vector<mint>> x, ll n) {
  ll k = x.size();
  vector<vector<mint>> ans(k, vector<mint>(k, 0));
  for (int i = 0; i < k; i++)
    ans[i][i] = 1;
  while (n != 0) {
    if (n & 1)
      ans = mul(ans, x);
    x = mul(x, x);
    n = n >> 1;
  }
  return ans;
}

template <typename Monoid, typename OperatorMonoid = Monoid>
struct LazySegmentTree {
  using F = function<Monoid(Monoid, Monoid)>;
  using G = function<Monoid(Monoid, OperatorMonoid)>;
  using H = function<OperatorMonoid(OperatorMonoid, OperatorMonoid)>;

  int sz, height;
  vector<Monoid> data;
  vector<OperatorMonoid> lazy;
  const F f;
  const G g;
  const H h;
  const Monoid M1;
  const OperatorMonoid OM0;

  LazySegmentTree(int n, const F f, const G g, const H h, const Monoid &M1,
                  const OperatorMonoid OM0)
      : f(f), g(g), h(h), M1(M1), OM0(OM0) {
    sz = 1;
    height = 0;
    while (sz < n)
      sz <<= 1, height++;
    data.assign(2 * sz, M1);
    lazy.assign(2 * sz, OM0);
  }

  void set(int k, const Monoid &x) { data[k + sz] = x; }

  void build() {
    for (int k = sz - 1; k > 0; k--) {
      data[k] = f(data[2 * k + 0], data[2 * k + 1]);
    }
  }

  inline void propagate(int k) {
    if (lazy[k] != OM0) {
      lazy[2 * k + 0] = h(lazy[2 * k + 0], lazy[k]);
      lazy[2 * k + 1] = h(lazy[2 * k + 1], lazy[k]);
      data[k] = reflect(k);
      lazy[k] = OM0;
    }
  }

  inline Monoid reflect(int k) {
    return lazy[k] == OM0 ? data[k] : g(data[k], lazy[k]);
  }

  inline void recalc(int k) {
    while (k >>= 1)
      data[k] = f(reflect(2 * k + 0), reflect(2 * k + 1));
  }

  inline void thrust(int k) {
    for (int i = height; i > 0; i--)
      propagate(k >> i);
  }

  void update(int a, int b, const OperatorMonoid &x) {
    thrust(a += sz);
    thrust(b += sz - 1);
    for (int l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {
      if (l & 1)
        lazy[l] = h(lazy[l], x), ++l;
      if (r & 1)
        --r, lazy[r] = h(lazy[r], x);
    }
    recalc(a);
    recalc(b);
  }

  Monoid query(int a, int b) {
    thrust(a += sz);
    thrust(b += sz - 1);
    Monoid L = M1, R = M1;
    for (int l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {
      if (l & 1)
        L = f(L, reflect(l++));
      if (r & 1)
        R = f(reflect(--r), R);
    }
    return f(L, R);
  }

  Monoid operator[](const int &k) { return query(k, k + 1); }

  template <typename C>
  int find_subtree(int a, const C &check, Monoid &M, bool type) {
    while (a < sz) {
      propagate(a);
      Monoid nxt =
          type ? f(reflect(2 * a + type), M) : f(M, reflect(2 * a + type));
      if (check(nxt))
        a = 2 * a + type;
      else
        M = nxt, a = 2 * a + 1 - type;
    }
    return a - sz;
  }

  template <typename C> int find_first(int a, const C &check) {
    Monoid L = M1;
    if (a <= 0) {
      if (check(f(L, reflect(1))))
        return find_subtree(1, check, L, false);
      return -1;
    }
    thrust(a + sz);
    int b = sz;
    for (a += sz, b += sz; a < b; a >>= 1, b >>= 1) {
      if (a & 1) {
        Monoid nxt = f(L, reflect(a));
        if (check(nxt))
          return find_subtree(a, check, L, false);
        L = nxt;
        ++a;
      }
    }
    return -1;
  }

  template <typename C> int find_last(int b, const C &check) {
    Monoid R = M1;
    if (b >= sz) {
      if (check(f(reflect(1), R)))
        return find_subtree(1, check, R, true);
      return -1;
    }
    thrust(b + sz - 1);
    int a = sz;
    for (b += sz; a < b; a >>= 1, b >>= 1) {
      if (b & 1) {
        Monoid nxt = f(reflect(--b), R);
        if (check(nxt))
          return find_subtree(b, check, R, true);
        R = nxt;
      }
    }
    return -1;
  }
};

int main() {
  M = 998244353;
  ll n, q;
  cin >> n >> q;
  function<pair<mint, ll>(pair<mint, ll>, pair<mint, ll>)> f =
      [](pair<mint, ll> a, pair<mint, ll> b) {
        return mp(a.first * mpow(10, b.second) + b.first, a.second + b.second);
      };
  function<pair<mint, ll>(pair<mint, ll>, mint)> g = [](pair<mint, ll> a,
                                                        mint x) {
    if (x != 0)
      return mp(x * (mpow(10, a.second) - 1) / 9, a.second);
    else
      return a;
  };
  function<mint(mint, mint)> h = [](mint a, mint b) {
    if (b != 0)
      return b;
    else
      return a;
  };
  LazySegmentTree<pair<mint, ll>, mint> seg(n, f, g, h, mp(0, 0), 0);
  rep(i, n) seg.set(i, mp(1, 1));
  seg.build();
  rep(i, q) {
    ll l, r, d;
    cin >> l >> r >> d;
    seg.update(--l, r, d);
    cout << seg.query(0, n).first << endl;
  }
}