Problem p02644 (C++) — buggy submission, verdict: Time Limit Exceeded

#ifdef LOCAL
// #define _GLIBCXX_DEBUG
#endif
// #pragma GCC target("avx512f,avx512dq,avx512cd,avx512bw,avx512vl")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<int, int> Pi;
typedef vector<ll> Vec;
typedef vector<int> Vi;
typedef vector<string> Vs;
typedef vector<P> VP;
typedef vector<vector<ll>> VV;
typedef vector<vector<int>> VVi;
typedef vector<vector<vector<ll>>> VVV;
typedef vector<vector<vector<vector<ll>>>> VVVV;

#define REP(i, a, b) for (ll i = (a); i < (b); i++)
#define PER(i, a, b) for (ll i = (a); i >= (b); i--)
#define rep(i, n) REP(i, 0, n)
#define per(i, n) PER(i, n, 0)
const ll INF = 1e18 + 18;
const ll MOD = 1000000007;
#define Yes(n) cout << ((n) ? "Yes" : "No") << endl;
#define YES(n) cout << ((n) ? "YES" : "NO") << endl;
#define ALL(v) v.begin(), v.end()
#define rALL(v) v.rbegin(), v.rend()
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a, b)
#define Each(a, b) for (auto &a : b)
#define rEach(i, mp) for (auto i = mp.rbegin(); i != mp.rend(); ++i)
#ifdef LOCAL
#define dbg(x_) cerr << #x_ << ":" << x_ << endl;
#define dbgmap(mp)                                                             \\
  cerr << #mp << ":" << endl;                                                  \\
  for (auto i = mp.begin(); i != mp.end(); ++i) {                              \\
    cerr << i->first << ":" << i->second << endl;                              \\
  }
#define dbgarr(n, m, arr)                                                      \\
  rep(i, n) {                                                                  \\
    rep(j, m) { cerr << arr[i][j] << " "; }                                    \\
    cerr << endl;                                                              \\
  }
#define dbgdp(n, arr)                                                          \\
  rep(i, n) { cerr << arr[i] << " "; }                                         \\
  cerr << endl;
#define dbgmint(n, arr)                                                        \\
  rep(i, n) { cerr << arr[i].x << " "; }                                       \\
  cerr << endl;
#define dbgarrmint(n, m, arr)                                                  \\
  rep(i, n) {                                                                  \\
    rep(j, m) { cerr << arr[i][j].x << " "; }                                  \\
    cerr << endl;                                                              \\
  }
#else
#define dbg(...)
#define dbgmap(...)
#define dbgarr(...)
#define dbgdp(...)
#define dbgmint(...)
#define dbgarrmint(...)
#endif
#define out(a) cout << a << endl
#define out2(a, b) cout << a << " " << b << endl
#define vout(v)                                                                \\
  rep(i, v.size()) { cout << v[i] << " "; }                                    \\
  cout << endl
#define Uniq(v) v.erase(unique(v.begin(), v.end()), v.end())
#define fi first
#define se second

template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> bool chmin(T &a, const T &b) {
  if (b < a) {
    a = b;
    return true;
  }
  return false;
}

template <typename T1, typename T2>
ostream &operator<<(ostream &s, const pair<T1, T2> &p) {
  return s << "(" << p.first << ", " << p.second << ")";
}

template <typename T> istream &operator>>(istream &i, vector<T> &v) {
  rep(j, v.size()) i >> v[j];
  return i;
}

// vector
template <typename T> ostream &operator<<(ostream &s, const vector<T> &v) {
  int len = v.size();
  for (int i = 0; i < len; ++i) {
    s << v[i];
    if (i < len - 1)
      s << "	";
  }
  return s;
}

// 2 dimentional vector
template <typename T>
ostream &operator<<(ostream &s, const vector<vector<T>> &vv) {
  int len = vv.size();
  for (int i = 0; i < len; ++i) {
    s << vv[i] << endl;
  }
  return s;
}

void dijkstra(vector<VP> g, ll start, Vec &dist) {
  priority_queue<P, vector<P>, function<bool(P, P)>> q(
      [](P a, P b) -> ll { return a.second > b.second; });
  dist[start] = 0;
  q.push(mp(start, 0));
  while (!q.empty()) {
    P now = q.top();
    q.pop();
    Each(nxt, g[now.fi]) {
      if (chmin(dist[nxt.fi], now.se + nxt.se)) {
        q.push(mp(nxt.fi, dist[nxt.fi]));
      }
    }
  }
}

int solve() {
  ll h, w, k;
  cin >> h >> w >> k;
  ll sy, sx, gy, gx;
  cin >> sy >> sx >> gy >> gx;
  sy--;
  sx--;
  gy--;
  gx--;
  vector<vector<char>> g(h, vector<char>(w));
  rep(i, h) {
    rep(j, w) { cin >> g[i][j]; }
  }
  // h,w,K
  VVV dist(h, VV(w, Vec(4, INF)));
  VVV process(h, VV(w, Vec(4, INF)));
  auto in = [&](ll y, ll x) { return y >= 0 && y < h && x >= 0 && x < w; };
  // queue<pair<P,P>> q;
  priority_queue<pair<P, P>, vector<pair<P, P>>,
                 function<bool(pair<P, P>, pair<P, P>)>>
      q([](pair<P, P> a, pair<P, P> b) -> ll { return a.se.se > b.se.se; });

  Vec dx = {1, 0, -1, 0, 1, -1, 1, -1};
  Vec dy = {0, 1, 0, -1, 1, 1, -1, -1};
  rep(i, 4) {
    dist[sy][sx][i] = 1;
    process[sy][sx][i] = 0;
    q.push(mp(mp(sy, sx), mp(i, 1LL)));
  }

  while (!q.empty()) {
    pair<P, P> pp = q.top();
    q.pop();
    auto [y, x] = pp.fi;
    auto [pre, pred] = pp.se;
    ll &proc = process[y][x][pre];
    rep(dir, 4) {
      ll ny = y + dy[dir];
      ll nx = x + dx[dir];
      if (!in(ny, nx))
        continue;
      if (g[ny][nx] == '@')
        continue;

      // 方向同じ
      if (pre == dir && proc < k) {
        if (chmin(dist[ny][nx][dir], pred)) {
          q.emplace(mp(ny, nx), mp(dir, dist[ny][nx][dir]));
          process[ny][nx][dir] = proc + 1;
        } else if (dist[ny][nx][dir] == pred) {
          if (chmin(process[ny][nx][dir], proc + 1)) {
            q.emplace(mp(ny, nx), mp(dir, dist[ny][nx][dir]));
          }
        }
      } else {
        if (chmin(dist[ny][nx][dir], pred + 1)) {
          q.emplace(mp(ny, nx), mp(dir, dist[ny][nx][dir]));
          process[ny][nx][dir] = 1;
        } else if (dist[ny][nx][dir] == dist[y][x][dir] + 1) {
          if (chmin(process[ny][nx][dir], 1LL)) {
            q.emplace(mp(ny, nx), mp(dir, dist[ny][nx][dir]));
          }
        }
      }
    }
  }
  ll ans = INF;
  //    rep(i,4){
  //        rep(ih,h){
  //            rep(iw,w){
  //                cerr<<dist[ih][iw][i]<< " ";
  //            }
  //            cerr<<endl;
  //        }
  //    }
  //    rep(i,4){
  //        rep(ih,h){
  //            rep(iw,w){
  //                cerr<<process[ih][iw][i]<< " ";
  //            }
  //            cerr<<endl;
  //        }
  //    }
  rep(i, 4) { chmin(ans, dist[gy][gx][i]); }
  if (ans == INF) {
    out(-1);
  } else {
    out(ans);
  }
  return 0;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << std::setprecision(10);
  solve();
}


Error: TLE

Fixed submission:

#ifdef LOCAL
// #define _GLIBCXX_DEBUG
#endif
// #pragma GCC target("avx512f,avx512dq,avx512cd,avx512bw,avx512vl")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<int, int> Pi;
typedef vector<ll> Vec;
typedef vector<int> Vi;
typedef vector<string> Vs;
typedef vector<P> VP;
typedef vector<vector<ll>> VV;
typedef vector<vector<int>> VVi;
typedef vector<vector<vector<ll>>> VVV;
typedef vector<vector<vector<vector<ll>>>> VVVV;

#define REP(i, a, b) for (ll i = (a); i < (b); i++)
#define PER(i, a, b) for (ll i = (a); i >= (b); i--)
#define rep(i, n) REP(i, 0, n)
#define per(i, n) PER(i, n, 0)
const ll INF = 1e18 + 18;
const ll MOD = 1000000007;
#define Yes(n) cout << ((n) ? "Yes" : "No") << endl;
#define YES(n) cout << ((n) ? "YES" : "NO") << endl;
#define ALL(v) v.begin(), v.end()
#define rALL(v) v.rbegin(), v.rend()
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a, b)
#define Each(a, b) for (auto &a : b)
#define rEach(i, mp) for (auto i = mp.rbegin(); i != mp.rend(); ++i)
#ifdef LOCAL
#define dbg(x_) cerr << #x_ << ":" << x_ << endl;
#define dbgmap(mp)                                                             \\
  cerr << #mp << ":" << endl;                                                  \\
  for (auto i = mp.begin(); i != mp.end(); ++i) {                              \\
    cerr << i->first << ":" << i->second << endl;                              \\
  }
#define dbgarr(n, m, arr)                                                      \\
  rep(i, n) {                                                                  \\
    rep(j, m) { cerr << arr[i][j] << " "; }                                    \\
    cerr << endl;                                                              \\
  }
#define dbgdp(n, arr)                                                          \\
  rep(i, n) { cerr << arr[i] << " "; }                                         \\
  cerr << endl;
#define dbgmint(n, arr)                                                        \\
  rep(i, n) { cerr << arr[i].x << " "; }                                       \\
  cerr << endl;
#define dbgarrmint(n, m, arr)                                                  \\
  rep(i, n) {                                                                  \\
    rep(j, m) { cerr << arr[i][j].x << " "; }                                  \\
    cerr << endl;                                                              \\
  }
#else
#define dbg(...)
#define dbgmap(...)
#define dbgarr(...)
#define dbgdp(...)
#define dbgmint(...)
#define dbgarrmint(...)
#endif
#define out(a) cout << a << endl
#define out2(a, b) cout << a << " " << b << endl
#define vout(v)                                                                \\
  rep(i, v.size()) { cout << v[i] << " "; }                                    \\
  cout << endl
#define Uniq(v) v.erase(unique(v.begin(), v.end()), v.end())
#define fi first
#define se second

template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T> bool chmin(T &a, const T &b) {
  if (b < a) {
    a = b;
    return true;
  }
  return false;
}

template <typename T1, typename T2>
ostream &operator<<(ostream &s, const pair<T1, T2> &p) {
  return s << "(" << p.first << ", " << p.second << ")";
}

template <typename T> istream &operator>>(istream &i, vector<T> &v) {
  rep(j, v.size()) i >> v[j];
  return i;
}

// vector
template <typename T> ostream &operator<<(ostream &s, const vector<T> &v) {
  int len = v.size();
  for (int i = 0; i < len; ++i) {
    s << v[i];
    if (i < len - 1)
      s << "	";
  }
  return s;
}

// 2 dimentional vector
template <typename T>
ostream &operator<<(ostream &s, const vector<vector<T>> &vv) {
  int len = vv.size();
  for (int i = 0; i < len; ++i) {
    s << vv[i] << endl;
  }
  return s;
}

void dijkstra(vector<VP> g, ll start, Vec &dist) {
  priority_queue<P, vector<P>, function<bool(P, P)>> q(
      [](P a, P b) -> ll { return a.second > b.second; });
  dist[start] = 0;
  q.push(mp(start, 0));
  while (!q.empty()) {
    P now = q.top();
    q.pop();
    Each(nxt, g[now.fi]) {
      if (chmin(dist[nxt.fi], now.se + nxt.se)) {
        q.push(mp(nxt.fi, dist[nxt.fi]));
      }
    }
  }
}

int solve() {
  ll h, w, k;
  cin >> h >> w >> k;
  ll sy, sx, gy, gx;
  cin >> sy >> sx >> gy >> gx;
  sy--;
  sx--;
  gy--;
  gx--;
  vector<vector<char>> g(h, vector<char>(w));
  rep(i, h) {
    rep(j, w) { cin >> g[i][j]; }
  }
  // h,w,K
  VVV dist(h, VV(w, Vec(4, INF)));
  VVV process(h, VV(w, Vec(4, INF)));
  auto in = [&](ll y, ll x) { return y >= 0 && y < h && x >= 0 && x < w; };
  // queue<pair<P,P>> q;
  priority_queue<pair<P, P>, vector<pair<P, P>>,
                 function<bool(pair<P, P>, pair<P, P>)>>
      q([](pair<P, P> a, pair<P, P> b) -> ll { return a.se.se > b.se.se; });

  Vec dx = {1, 0, -1, 0, 1, -1, 1, -1};
  Vec dy = {0, 1, 0, -1, 1, 1, -1, -1};
  rep(i, 4) {
    dist[sy][sx][i] = 1;
    process[sy][sx][i] = 0;
    q.push(mp(mp(sy, sx), mp(i, 1LL)));
  }

  while (!q.empty()) {
    pair<P, P> pp = q.top();
    q.pop();
    auto [y, x] = pp.fi;
    auto [pre, pred] = pp.se;
    ll &proc = process[y][x][pre];
    rep(dir, 4) {
      ll ny = y + dy[dir];
      ll nx = x + dx[dir];
      if (!in(ny, nx))
        continue;
      if (g[ny][nx] == '@')
        continue;

      // 方向同じ
      if (pre == dir && proc < k) {
        if (chmin(dist[ny][nx][dir], pred)) {
          q.emplace(mp(ny, nx), mp(dir, dist[ny][nx][dir]));
          process[ny][nx][dir] = proc + 1;
        }
      } else {
        if (chmin(dist[ny][nx][dir], pred + 1)) {
          q.emplace(mp(ny, nx), mp(dir, dist[ny][nx][dir]));
          process[ny][nx][dir] = 1;
        }
        //                else if(dist[ny][nx][dir]==dist[y][x][dir]+1){
        //                    if(chmin(process[ny][nx][dir],1LL)){
        //                        q.emplace(mp(ny,nx),mp(dir,dist[ny][nx][dir]));
        //                    }
        //                }
      }
    }
  }
  ll ans = INF;
  rep(i, 4) {
    rep(ih, h) {
      rep(iw, w) { cerr << dist[ih][iw][i] << " "; }
      cerr << endl;
    }
  }
  rep(i, 4) {
    rep(ih, h) {
      rep(iw, w) { cerr << process[ih][iw][i] << " "; }
      cerr << endl;
    }
  }
  rep(i, 4) { chmin(ans, dist[gy][gx][i]); }
  if (ans == INF) {
    out(-1);
  } else {
    out(ans);
  }
  return 0;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << std::setprecision(10);
  solve();
}