Problem p03819 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <bits/stdc++.h>

#define _overload(_1, _2, _3, name, ...) name
#define _rep(i, n) _range(i, 0, n)
#define _range(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rep(...) _overload(__VA_ARGS__, _range, _rep, )(__VA_ARGS__)

#define _rrep(i, n) _rrange(i, n, 0)
#define _rrange(i, a, b) for (int i = (int)(a)-1; i >= (int)(b); --i)
#define rrep(...) _overload(__VA_ARGS__, _rrange, _rrep, )(__VA_ARGS__)

#define _all(arg) begin(arg), end(arg)
#define uniq(arg) sort(_all(arg)), (arg).erase(unique(_all(arg)), end(arg))
#define getidx(ary, key) lower_bound(_all(ary), key) - begin(ary)
#define clr(a, b) memset((a), (b), sizeof(a))
#define bit(n) (1LL << (n))

// #define DEBUG

#ifdef DEBUG
#define dump(...) fprintf(stderr, __VA_ARGS__)
#else
#define dump(...)
#endif

template <class T> bool chmax(T &a, const T &b) {
  return (a < b) ? (a = b, 1) : 0;
}
template <class T> bool chmin(T &a, const T &b) {
  return (b < a) ? (a = b, 1) : 0;
}

using namespace std;
using ll = long long;
using vi = vector<int>;
using vll = vector<ll>;

const double EPS = 1e-10;
const double PI = acos(-1.0);
const ll inf = 1LL << 62;
const ll mod = 1000000007LL;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

ll extgcd(ll a, ll b, ll &x, ll &y) {
  x = 1, y = 0;
  ll g = a;
  if (b != 0)
    g = extgcd(b, a % b, y, x), y -= a / b * x;
  return g;
}
ll ADD(const ll &a, const ll &b, const ll &mod) { return (a + b) % mod; }
ll SUB(const ll &a, const ll &b, const ll &mod) { return (a - b + mod) % mod; }
ll MUL(const ll &a, const ll &b, const ll &mod) { return (1LL * a * b) % mod; }
ll DIV(const ll &a, const ll &b, const ll &mod) {
  ll x, y;
  extgcd(b, mod, x, y);
  return MUL(a, (x + mod) % mod, mod);
}

random_device rd;
mt19937 mt(rd());
uniform_int_distribution<int> dice(1, 6);
uniform_real_distribution<double> score(0.0, 10.0);

struct SegTree {
  vi node, lazy;
  int n;

  int get_c1(int k) { return 2 * k + 1; }
  int get_c2(int k) { return 2 * k + 2; }

  int pow2fit(int x) {
    int ret = 1;
    while (ret < x)
      ret *= 2;
    return ret;
  }

  SegTree(int sz) {
    n = pow2fit(sz);
    node = lazy = vi(2 * n);
  }

  void update(int k) {
    if (lazy[k] == 0)
      return;
    node[k] += lazy[k];
    int c1 = get_c1(k);
    int c2 = get_c2(k);
    if (k < n) {
      lazy[c1] += lazy[k] / 2;
      lazy[c2] += lazy[k] / 2;
    }
    lazy[k] = 0;
  }

  // [a, b)
  void add(int a, int b, int x, int k = 0, int l = 0, int r = -1) {
    if (r < 0)
      r = n;

    update(k);
    if (a >= r or l >= b)
      return;
    if (a <= l and r <= b) {
      lazy[k] = (r - l) * x;
      update(k);
      return;
    }

    add(a, b, x, get_c1(k), l, (l + r) / 2);
    add(a, b, x, get_c2(k), (l + r) / 2, r);
    node[k] = node[get_c1(k)] + node[get_c2(k)];
  }

  // [a, b)
  int get_sum(int a, int b, int k = 0, int l = 0, int r = -1) {
    if (r < 0)
      r = n;

    update(k);
    if (a >= r or l >= b)
      return 0;
    if (a <= l and r <= b)
      return node[k];

    return get_sum(a, b, get_c1(k), l, (l + r) / 2) +
           get_sum(a, b, get_c2(k), (l + r) / 2, r);
  }
};

int main(void) {
  cin.tie(0);
  ios::sync_with_stdio(false);

  int n, m;
  cin >> n >> m;
  using Elem = tuple<int, int, int>;
  vector<Elem> in(n);
  rep(i, n) {
    int l, r;
    cin >> l >> r;
    r++;
    in[i] = Elem(r - l, l, r);
  }
  sort(_all(in));

  int tr = n, idx = 0;
  SegTree seg(m + 1);
  rep(d, 1, m + 1) {
    while (idx < n) {
      int len, l, r;
      tie(len, l, r) = in[idx];
      if (len >= d)
        break;
      seg.add(l, r, 1);
      tr--, idx++;
    }
    if (tr == n) {
      cout << n << endl;
      continue;
    }
    rep(i, 1, m + 1) { seg.get_sum(i, i + 1); }

    int cur = 0;
    int res = tr;
    while (cur <= m) {
      res += seg.get_sum(cur, cur + 1);
      cur += d;
    }
    cout << res << endl;
  }

  return 0;
}


Fixed submission:
#include <bits/stdc++.h>

#define _overload(_1, _2, _3, name, ...) name
#define _rep(i, n) _range(i, 0, n)
#define _range(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rep(...) _overload(__VA_ARGS__, _range, _rep, )(__VA_ARGS__)

#define _rrep(i, n) _rrange(i, n, 0)
#define _rrange(i, a, b) for (int i = (int)(a)-1; i >= (int)(b); --i)
#define rrep(...) _overload(__VA_ARGS__, _rrange, _rrep, )(__VA_ARGS__)

#define _all(arg) begin(arg), end(arg)
#define uniq(arg) sort(_all(arg)), (arg).erase(unique(_all(arg)), end(arg))
#define getidx(ary, key) lower_bound(_all(ary), key) - begin(ary)
#define clr(a, b) memset((a), (b), sizeof(a))
#define bit(n) (1LL << (n))

// #define DEBUG

#ifdef DEBUG
#define dump(...) fprintf(stderr, __VA_ARGS__)
#else
#define dump(...)
#endif

template <class T> bool chmax(T &a, const T &b) {
  return (a < b) ? (a = b, 1) : 0;
}
template <class T> bool chmin(T &a, const T &b) {
  return (b < a) ? (a = b, 1) : 0;
}

using namespace std;
using ll = long long;
using vi = vector<int>;
using vll = vector<ll>;

const double EPS = 1e-10;
const double PI = acos(-1.0);
const ll inf = 1LL << 62;
const ll mod = 1000000007LL;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

ll extgcd(ll a, ll b, ll &x, ll &y) {
  x = 1, y = 0;
  ll g = a;
  if (b != 0)
    g = extgcd(b, a % b, y, x), y -= a / b * x;
  return g;
}
ll ADD(const ll &a, const ll &b, const ll &mod) { return (a + b) % mod; }
ll SUB(const ll &a, const ll &b, const ll &mod) { return (a - b + mod) % mod; }
ll MUL(const ll &a, const ll &b, const ll &mod) { return (1LL * a * b) % mod; }
ll DIV(const ll &a, const ll &b, const ll &mod) {
  ll x, y;
  extgcd(b, mod, x, y);
  return MUL(a, (x + mod) % mod, mod);
}

random_device rd;
mt19937 mt(rd());
uniform_int_distribution<int> dice(1, 6);
uniform_real_distribution<double> score(0.0, 10.0);

struct SegTree {
  vi node, lazy;
  int n;

  int get_c1(int k) { return 2 * k + 1; }
  int get_c2(int k) { return 2 * k + 2; }

  int pow2fit(int x) {
    int ret = 1;
    while (ret < x)
      ret *= 2;
    return ret;
  }

  SegTree(int sz) {
    n = pow2fit(sz);
    node = lazy = vi(2 * n);
  }

  void update(int k) {
    if (lazy[k] == 0)
      return;
    node[k] += lazy[k];
    int c1 = get_c1(k);
    int c2 = get_c2(k);
    if (k < n) {
      lazy[c1] += lazy[k] / 2;
      lazy[c2] += lazy[k] / 2;
    }
    lazy[k] = 0;
  }

  // [a, b)
  void add(int a, int b, int x, int k = 0, int l = 0, int r = -1) {
    if (r < 0)
      r = n;

    update(k);
    if (a >= r or l >= b)
      return;
    if (a <= l and r <= b) {
      lazy[k] = (r - l) * x;
      update(k);
      return;
    }

    add(a, b, x, get_c1(k), l, (l + r) / 2);
    add(a, b, x, get_c2(k), (l + r) / 2, r);
    node[k] = node[get_c1(k)] + node[get_c2(k)];
  }

  // [a, b)
  int get_sum(int a, int b, int k = 0, int l = 0, int r = -1) {
    if (r < 0)
      r = n;

    update(k);
    if (a >= r or l >= b)
      return 0;
    if (a <= l and r <= b)
      return node[k];

    return get_sum(a, b, get_c1(k), l, (l + r) / 2) +
           get_sum(a, b, get_c2(k), (l + r) / 2, r);
  }
};

int main(void) {
  cin.tie(0);
  ios::sync_with_stdio(false);

  int n, m;
  cin >> n >> m;
  using Elem = tuple<int, int, int>;
  vector<Elem> in(n);
  rep(i, n) {
    int l, r;
    cin >> l >> r;
    r++;
    in[i] = Elem(r - l, l, r);
  }
  sort(_all(in));

  int tr = n, idx = 0;
  SegTree seg(m + 1);
  rep(d, 1, m + 1) {
    while (idx < n) {
      int len, l, r;
      tie(len, l, r) = in[idx];
      if (len >= d)
        break;
      seg.add(l, r, 1);
      tr--, idx++;
    }
    if (tr == n) {
      cout << n << endl;
      continue;
    }

    int cur = 0;
    int res = tr;
    while (cur <= m) {
      res += seg.get_sum(cur, cur + 1);
      cur += d;
    }
    cout << res << endl;
  }

  return 0;
}