Problem p02726 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using VI = vector<int>;
using VL = vector<ll>;
using VS = vector<string>;
template <class T> using PQ = priority_queue<T, vector<T>, greater<T>>;
#define FOR(i, a, n) for (int(i) = (a); (i) < (n); ++(i))
#define eFOR(i, a, n) for (int(i) = (a); (i) <= (n); ++(i))
#define rFOR(i, a, n) for (int(i) = (n)-1; (i) >= (a); --(i))
#define erFOR(i, a, n) for (int(i) = (n); (i) >= (a); --(i))
#define each(i, a) for (auto &i : a)
#define SORT(i) sort((i).begin(), (i).end())
#define rSORT(i, a) sort((i).begin(), (i).end(), (a))
#define all(i) (i).begin(), (i).end()
#define out(y, x) ((y) < 0 || h <= (y) || (x) < 0 || w <= (x))
#define line cout << "-----------------------------\\n"
#define ENDL(i, n) ((i) == (n)-1 ? "\\n" : " ")
#define stop system("pause") // comment out this on AOJ.
constexpr ll INF = 1000000000;
constexpr ll LLINF = 1LL << 60;
constexpr ll mod = 1000000007;
constexpr ll MOD = 998244353;
constexpr ld eps = 1e-10;
constexpr ld pi = 3.1415926535897932;
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
inline void init() {
  cin.tie(nullptr);
  cout.tie(nullptr);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(15);
}
template <class T> inline istream &operator>>(istream &is, vector<T> &v) {
  for (auto &elemnt : v)
    is >> elemnt;
  return is;
}
template <class T> inline istream &operator>>(istream &is, deque<T> &v) {
  for (auto &elemnt : v)
    is >> elemnt;
  return is;
}
template <class T, class U>
inline istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first >> p.second;
  return is;
}
template <class T> inline vector<T> vec(size_t a) { return vector<T>(a); }
template <class T> inline vector<T> defvec(T def, size_t a) {
  return vector<T>(a, def);
}
template <class T, class... Ts> inline auto vec(size_t a, Ts... ts) {
  return vector<decltype(vec<T>(ts...))>(a, vec<T>(ts...));
}
template <class T, class... Ts> inline auto defvec(T def, size_t a, Ts... ts) {
  return vector<decltype(defvec<T>(def, ts...))>(a, defvec<T>(def, ts...));
}

int main() {
  init();

  int n, x, y;
  cin >> n >> x >> y;
  --x, --y;
  vector<VI> g(n);
  FOR(i, 1, n) {
    g[i - 1].push_back(i);
    g[i].push_back(i - 1);
  }
  g[x].push_back(y);
  g[y].push_back(x);

  VI ans(n);

  auto dis = defvec<int>(INF, n, n);
  PQ<pair<ll, int>> dik;
  FOR(i, 0, n) {
    dis[i][i] = 0;
    dik.emplace(0, i);
    while (!dik.empty()) {
      int d, now;
      tie(d, now) = dik.top();
      dik.pop();
      if (dis[i][now] < d)
        continue;
      each(to, g[now]) {
        if (!chmin(dis[i][to], d + 1))
          continue;
        dik.emplace(d + 1, to);
      }
    }
    FOR(j, i, n)++ ans[dis[i][j]];
  }

  FOR(i, 1, n) cout << ans[i] << "\\n";
}


Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using VI = vector<int>;
using VL = vector<ll>;
using VS = vector<string>;
template <class T> using PQ = priority_queue<T, vector<T>, greater<T>>;
#define FOR(i, a, n) for (int(i) = (a); (i) < (n); ++(i))
#define eFOR(i, a, n) for (int(i) = (a); (i) <= (n); ++(i))
#define rFOR(i, a, n) for (int(i) = (n)-1; (i) >= (a); --(i))
#define erFOR(i, a, n) for (int(i) = (n); (i) >= (a); --(i))
#define each(i, a) for (auto &i : a)
#define SORT(i) sort((i).begin(), (i).end())
#define rSORT(i, a) sort((i).begin(), (i).end(), (a))
#define all(i) (i).begin(), (i).end()
#define out(y, x) ((y) < 0 || h <= (y) || (x) < 0 || w <= (x))
#define line cout << "-----------------------------\\n"
#define ENDL(i, n) ((i) == (n)-1 ? "\\n" : " ")
#define stop system("pause") // comment out this on AOJ.
constexpr ll INF = 1000000000;
constexpr ll LLINF = 1LL << 60;
constexpr ll mod = 1000000007;
constexpr ll MOD = 998244353;
constexpr ld eps = 1e-10;
constexpr ld pi = 3.1415926535897932;
template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
inline void init() {
  cin.tie(nullptr);
  cout.tie(nullptr);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(15);
}
template <class T> inline istream &operator>>(istream &is, vector<T> &v) {
  for (auto &elemnt : v)
    is >> elemnt;
  return is;
}
template <class T> inline istream &operator>>(istream &is, deque<T> &v) {
  for (auto &elemnt : v)
    is >> elemnt;
  return is;
}
template <class T, class U>
inline istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first >> p.second;
  return is;
}
template <class T> inline vector<T> vec(size_t a) { return vector<T>(a); }
template <class T> inline vector<T> defvec(T def, size_t a) {
  return vector<T>(a, def);
}
template <class T, class... Ts> inline auto vec(size_t a, Ts... ts) {
  return vector<decltype(vec<T>(ts...))>(a, vec<T>(ts...));
}
template <class T, class... Ts> inline auto defvec(T def, size_t a, Ts... ts) {
  return vector<decltype(defvec<T>(def, ts...))>(a, defvec<T>(def, ts...));
}

int main() {
  init();

  int n, x, y;
  cin >> n >> x >> y;
  --x, --y;
  auto dis = defvec<int>(INF, n, n);
  FOR(i, 0, n) dis[i][i] = 0;
  FOR(i, 1, n) {
    dis[i - 1][i] = 1;
    dis[i][i - 1] = 1;
  }
  dis[x][y] = 1;
  dis[y][x] = 1;

  FOR(k, 0, n) FOR(i, 0, n) FOR(j, 0, n) {
    chmin(dis[i][j], dis[i][k] + dis[j][k]);
  }

  VI d(n);
  FOR(i, 0, n) FOR(j, i + 1, n)++ d[dis[i][j]];

  FOR(i, 1, n) cout << d[i] << "\\n";
}