Problem p02680 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/detail/standard_policies.hpp>
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
// v.erase(unique(v.begin(),v.end()),v.end());

#define ff first
#define ss second
#define fastio                                                                 \\
  ios_base::sync_with_stdio(false);                                            \\
  cin.tie(NULL)

typedef long double ld;
typedef long long ll;
const int N = 3550;
const ll mod = 998244353;
const int INF = 1e+9;
using namespace std;
// using namespace __gnu_pbds;

// typedef tree<pair<ll, ll>,null_type,less<pair<ll,
// ll>>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

#define TRACE
#ifdef TRACE
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1> void __f(const char *name, Arg1 &&arg1) {
  cerr << name << " : " << arg1 << endl;
}

template <typename Arg1, typename... Args>
void __f(const char *names, Arg1 &&arg1, Args &&...args) {
  const char *comma = strchr(names + 1, ',');
  cerr.write(names, comma - names) << " : " << arg1 << " | ";
  __f(comma + 1, args...);
}
#else
#define trace(...)
#endif

map<int, int> l, r;
ll d_l[N], d_r[N];
vector<int> la, ra;
vector<pair<int, pair<int, int>>> X, Y;
bool adj_l[N][N], adj_r[N][N], vis[N][N];
int curr1 = 1, curr2 = 1;

void llenar() {
  for (int i = 0; i < N; i++) {
    for (int j = 0; j < N; j++) {
      adj_l[i][j] = true;
      adj_r[i][j] = true;
    }
  }
}

ll bfs(int x, int y) {
  // vis[x][y] = true;
  queue<pair<int, int>> pq;
  pq.push({x, y});
  vis[x][y] = true;
  ll ans = 0;
  while (!pq.empty()) {
    int u = pq.front().ff;
    int v = pq.front().ss;
    pq.pop();
    if ((u <= 0) or (u >= (curr1 - 1)) or (v <= 0) or (v >= (curr2 - 1)))
      return -1;

    // trace(u, v, d_l[u], d_r[v]);
    ans += (ll)(d_l[u] * d_r[v]);

    // ahora visitamos llos cuatro lados

    if (adj_r[v][u] and !vis[u][v - 1]) {
      vis[u][v - 1] = true;
      pq.push({u, v - 1});
    }
    if (adj_r[v + 1][u] and !vis[u][v + 1]) {
      vis[u][v + 1] = true;
      pq.push({u, v + 1});
    }
    if (adj_l[u][v] and !vis[u - 1][v]) {
      vis[u - 1][v] = true;
      pq.push({u - 1, v});
    }
    if (adj_l[u + 1][v] and !vis[u + 1][v]) {
      vis[u + 1][v] = true;
      pq.push({u + 1, v});
    }
  }
  return ans;
}

void solve() {
  int n, m;
  cin >> n >> m;
  la.push_back(0);
  ra.push_back(0);
  for (int i = 0; i < n; i++) {
    int a, b, c;
    cin >> a >> b >> c;
    X.push_back({c, {a, b}});
    ra.push_back(c);
    la.push_back(a);
    la.push_back(b);
  }
  for (int i = 0; i < m; i++) {
    int d, e, f;
    cin >> d >> e >> f;
    Y.push_back({d, {e, f}});
    ra.push_back(e);
    ra.push_back(f);
    la.push_back(d);
  }

  sort(la.begin(), la.end());
  sort(ra.begin(), ra.end());
  la.erase(unique(la.begin(), la.end()), la.end());
  ra.erase(unique(ra.begin(), ra.end()), ra.end());
  // for(auto x: ra) trace(x);
  if ((la.size() <= 2) or (ra.size() <= 2)) {
    cout << "INF" << endl;
    return;
  }
  for (auto val : la)
    l[val] = curr1++;
  for (int i = 0; i < la.size() - 1; i++) {
    d_l[i + 1] = la[i + 1] - la[i];
  }

  for (auto val : ra)
    r[val] = curr2++;
  for (int i = 0; i < ra.size() - 1; i++) {
    d_r[i + 1] = ra[i + 1] - ra[i];
  }
  // trace(curr1, curr2);
  // for(int i = 0; i < 12; i++) trace(d_r[i]);
  // ya ahora tenemos mapeado todos las weadas

  llenar();

  // ahora recorremos de nuevo la mrd

  for (int i = 0; i < n; i++) {
    int a = X[i].ss.ff, b = X[i].ss.ss, c = X[i].ff;
    for (int j = l[a]; j < l[b]; j++)
      adj_r[r[c]][j] = false;
  }
  for (int i = 0; i < m; i++) {
    int d = Y[i].ff, e = Y[i].ss.ff, f = Y[i].ss.ss;
    for (int j = r[e]; j < r[f]; j++)
      adj_l[l[d]][j] = false;
  }
  /*
  for(int i = 0; i < 12; i++){
      for(int j = 0; j < 12; j++){
          if(adj_r[i][j]) cout << ".";
          else cout << "#";
      }
      cout << endl;
  }*/
  // ya llenamos los vacios de mrd que no se pueden cruzar xd

  // ahora el dfs
  // dfs(l[0], r[0]);
  ll uwu = bfs(l[0], r[0]);
  if (uwu != -1)
    cout << uwu << endl;
  else
    cout << "INF" << endl;
}

int main() {
  fastio;
  int tc = 1;
  // cin >> tc;

  while (tc--)
    solve();

  return 0;
}


Error: 0

Fixed submission:

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/detail/standard_policies.hpp>
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
// v.erase(unique(v.begin(),v.end()),v.end());

#define ff first
#define ss second
#define fastio                                                                 \\
  ios_base::sync_with_stdio(false);                                            \\
  cin.tie(NULL)

typedef long double ld;
typedef long long ll;
const int N = 3550;
const ll mod = 998244353;
const int INF = 1e+9;
using namespace std;
// using namespace __gnu_pbds;

// typedef tree<pair<ll, ll>,null_type,less<pair<ll,
// ll>>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

#define TRACE
#ifdef TRACE
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1> void __f(const char *name, Arg1 &&arg1) {
  cerr << name << " : " << arg1 << endl;
}

template <typename Arg1, typename... Args>
void __f(const char *names, Arg1 &&arg1, Args &&...args) {
  const char *comma = strchr(names + 1, ',');
  cerr.write(names, comma - names) << " : " << arg1 << " | ";
  __f(comma + 1, args...);
}
#else
#define trace(...)
#endif

map<int, int> l, r;
int d_l[N], d_r[N];
vector<int> la, ra;
vector<pair<int, pair<int, int>>> X, Y;
bool adj_l[N][N], adj_r[N][N], vis[N][N];
int curr1 = 1, curr2 = 1;
ll ans = 0;
bool wea = false;

void llenar() {
  for (int i = 0; i < N; i++) {
    for (int j = 0; j < N; j++) {
      adj_l[i][j] = true;
      adj_r[i][j] = true;
    }
  }
}

void dfs(int x, int y) {
  // vis[x][y] = true;
  if (wea or (x <= 0) or (x >= (curr1 - 1)) or (y <= 0) or (y >= (curr2 - 1))) {
    wea = true;
    return;
  }
  vis[x][y] = true;
  ans += (ll)(d_l[x]) * d_r[y];
  // ahora visitamos llos cuatro lados

  if (adj_r[y][x] and !vis[x][y - 1])
    dfs(x, y - 1);
  if (wea)
    return;
  if (adj_r[y + 1][x] and !vis[x][y + 1])
    dfs(x, y + 1);
  if (wea)
    return;
  if (adj_l[x][y] and !vis[x - 1][y])
    dfs(x - 1, y);
  if (wea)
    return;
  if (adj_l[x + 1][y] and !vis[x + 1][y])
    dfs(x + 1, y);
  if (wea)
    return;
}

void aver() {
  vector<int> nuev;
  nuev.clear();
  ra.push_back(1e+9 + 10);
  for (int i = 1; i < ra.size(); i++) {
    if (ra[i] != ra[i - 1])
      nuev.push_back(ra[i - 1]);
  }
  ra = nuev;
  nuev.clear();
  la.push_back(1e+9 + 10);
  for (int i = 1; i < la.size(); i++) {
    if (la[i] != la[i - 1])
      nuev.push_back(la[i - 1]);
  }
  la = nuev;
}

void solve() {
  int n, m;
  cin >> n >> m;
  la.push_back(0);
  ra.push_back(0);
  for (int i = 0; i < n; i++) {
    int a, b, c;
    cin >> a >> b >> c;
    X.push_back({c, {a, b}});
    ra.push_back(c);
    la.push_back(a);
    la.push_back(b);
  }
  for (int i = 0; i < m; i++) {
    int d, e, f;
    cin >> d >> e >> f;
    Y.push_back({d, {e, f}});
    ra.push_back(e);
    ra.push_back(f);
    la.push_back(d);
  }

  sort(la.begin(), la.end());
  sort(ra.begin(), ra.end());
  aver();
  // for(auto x: ra) trace(x);
  if ((la.size() <= 2) or (ra.size() <= 2)) {
    cout << "INF" << endl;
    return;
  }
  for (auto val : la)
    l[val] = curr1++;
  for (int i = 0; i < la.size() - 1; i++) {
    d_l[i + 1] = la[i + 1] - la[i];
  }

  for (auto val : ra)
    r[val] = curr2++;
  for (int i = 0; i < ra.size() - 1; i++) {
    d_r[i + 1] = ra[i + 1] - ra[i];
  }
  // trace(curr1, curr2);
  // for(int i = 0; i < 12; i++) trace(d_r[i]);
  // ya ahora tenemos mapeado todos las weadas

  llenar();

  // ahora recorremos de nuevo la mrd

  for (int i = 0; i < n; i++) {
    int a = X[i].ss.ff, b = X[i].ss.ss, c = X[i].ff;
    for (int j = l[a]; j < l[b]; j++)
      adj_r[r[c]][j] = false;
  }
  for (int i = 0; i < m; i++) {
    int d = Y[i].ff, e = Y[i].ss.ff, f = Y[i].ss.ss;
    for (int j = r[e]; j < r[f]; j++)
      adj_l[l[d]][j] = false;
  }
  /*
  for(int i = 0; i < 12; i++){
      for(int j = 0; j < 12; j++){
          if(adj_r[i][j]) cout << ".";
          else cout << "#";
      }
      cout << endl;
  }*/
  // ya llenamos los vacios de mrd que no se pueden cruzar xd

  // ahora el dfs
  dfs(l[0], r[0]);

  if (wea) {
    cout << "INF" << endl;
    return;
  }
  cout << ans << endl;
}

int main() {
  fastio;
  int tc = 1;
  // cin >> tc;

  while (tc--)
    solve();

  return 0;
}