Problem p01133 (C++) — buggy submission, verdict: Time Limit Exceeded

#define DEBUG_ON
#define CONDITION true
using namespace std; /*{{{*/

#include <algorithm>
#include <cassert>
#include <cctype>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <sys/time.h>
#include <vector>

#define INF (1e9)
static const double PI = acos(-1.0);
static const double EPS = 1e-10;

typedef long long int LL;
typedef unsigned long long int ULL;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<double> VD;
typedef vector<VD> VVD;
typedef vector<bool> VB;
typedef vector<VB> VVB;
typedef vector<char> VC;
typedef vector<VC> VVC;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef complex<double> P;

#define FOR(i, b, e) for (typeof(e) i = (b); i != (e); i < (e) ? ++i : --i)
#define REP(i, n) FOR(i, 0, n)

#define IFC(c)                                                                 \\
  if (c)                                                                       \\
    continue;
#define IFB(c)                                                                 \\
  if (c)                                                                       \\
    break;
#define IFR(c, r)                                                              \\
  if (c)                                                                       \\
    return r;

#define OPOVER(_op, _type) inline bool operator _op(const _type &t) const

#define arrsz(a) (sizeof(a) / sizeof(a[0]))

#define F first
#define S second
#define MP(a, b) make_pair(a, b)

#define SZ(a) ((LL)a.size())
#define PB(e) push_back(e)
#define SORT(v) sort((v).begin(), (v).end())
#define RSORT(v) sort((v).rbegin(), (v).rend())

#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define EACH(c, it)                                                            \\
  for (__typeof((c).begin()) it = (c).begin(); it != (c).end(); ++it)
#define EXIST(s, e) ((s).find(e) != (s).end())

#define BIT(n) (1ULL << (n))
#define BITOF(n, m) ((ULL)(n) >> (m)&1)

#define RANGE(a, b, c) ((a) <= (b) && (b) <= (c))

#define PQ priority_queue
#define SC static_cast

#ifdef DEBUG_ON
#define dprt(fmt, ...)                                                         \\
  if (CONDITION)                                                               \\
  fprintf(stderr, fmt, ##__VA_ARGS__)
#define darr(a)                                                                \\
  if (CONDITION)                                                               \\
    copy((a), (a) + arrsz(a), ostream_iterator<int>(cerr, " "));               \\
  cerr << endl
#define darr_range(a, f, t)                                                    \\
  if (CONDITION)                                                               \\
    copy((a) + (f), (a) + (t), ostream_iterator<int>(cerr, " "));              \\
  cerr << endl
#define dvec(v)                                                                \\
  if (CONDITION)                                                               \\
    copy(ALL(v), ostream_iterator<int>(cerr, " "));                            \\
  cerr << endl
#define darr2(a, n, m)                                                         \\
  if (CONDITION)                                                               \\
    FOR(i, 0, (n)) { darr_range((a)[i], 0, (m)); }
#define dvec2(v)                                                               \\
  if (CONDITION)                                                               \\
    FOR(i, 0, SZ(v)) { dvec((v)[i]); }
#define WAIT()                                                                 \\
  if (CONDITION) {                                                             \\
    string _wait_;                                                             \\
    cerr << "(hit return to continue)" << endl;                                \\
    getline(cin, _wait_);                                                      \\
  }
#define dump(x)                                                                \\
  if (CONDITION)                                                               \\
    cerr << " [L" << __LINE__ << "] " << #x << " = " << (x) << endl;
#define dumpf()                                                                \\
  if (CONDITION)                                                               \\
    cerr << __PRETTY_FUNCTION__ << endl;
#define dumpv(x)                                                               \\
  if (CONDITION)                                                               \\
    cerr << " [L:" << __LINE__ << "] " << #x << " = ";                         \\
  REP(q, (x).size()) cerr << (x)[q] << " ";                                    \\
  cerr << endl;
#define where()                                                                \\
  if (CONDITION)                                                               \\
    cerr << __FILE__ << ": " << __PRETTY_FUNCTION__ << " [L: " << __LINE__     \\
         << "]" << endl;
#define show_bits(b, s)                                                        \\
  if (CONDITION) {                                                             \\
    REP(i, s) {                                                                \\
      cerr << BITOF(b, s - 1 - i);                                             \\
      if (i % 4 == 3)                                                          \\
        cerr << ' ';                                                           \\
    }                                                                          \\
    cerr << endl;                                                              \\
  }
#else
#define cerr                                                                   \\
  if (0)                                                                       \\
  cerr
#define dprt(fmt, ...)
#define darr(a)
#define darr_range(a, f, t)
#define dvec(v)
#define darr2(a, n, m)
#define dvec2(v)
#define WAIT()
#define dump(x)
#define dumpf()
#define dumpv(x)
#define where()
#define show_bits(b, s)
#endif

/* Inline functions */
inline int onbits_count(ULL b) {
  int c = 0;
  while (b != 0) {
    c += (b & 1);
    b >>= 1;
  }
  return c;
}
inline int bits_count(ULL b) {
  int c = 0;
  while (b != 0) {
    ++c;
    b >>= 1;
  }
  return c;
}
inline int toInt(string s) {
  int v;
  istringstream sin(s);
  sin >> v;
  return v;
}
template <class T> inline string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}
inline double now() {
  struct timeval tv;
  gettimeofday(&tv, NULL);
  return (static_cast<double>(tv.tv_sec) +
          static_cast<double>(tv.tv_usec) * 1e-6);
}
inline VS split(string s, char delimiter) {
  VS v;
  string t;
  REP(i, s.length()) {
    if (s[i] == delimiter)
      v.PB(t), t = "";
    else
      t += s[i];
  }
  v.PB(t);
  return v;
}

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

/* Frequent stuffs */
int n_dir = 4;
enum direction { UP, RIGHT, DOWN, LEFT };
// int n_dir = 8;
// int dx[] = {0, 1, 1, 1, 0, -1, -1, -1}, dy[] = {-1, -1, 0, 1, 1, 1, 0, -1};
// enum direction {
// UP, UPRIGHT, RIGHT, DOWNRIGHT, DOWN, DOWNLEFT, LEFT, UPLEFT
// }
#define FORDIR(d) REP(d, n_dir)

/*}}}*/

int n, hx, hy, dx, dy;
VVD dist;
vector<P> cristals;
VD limits;

bool get_cristal(int status, int position, double time) {
  if (status == (1 << n) - 1) {
    return true;
  }

  // Stop searching if more than one cristal is not to be reached
  REP(c, n) {
    if ((status & (1 << c)) == 0) {
      if (time + dist[position][c] > limits[c] - EPS) {
        return false;
      }
    }
  }

  bool clear = false;
  REP(c, n) {
    if ((status & (1 << c)) == 0) {
      // Get c-th cristal
      if (get_cristal(status | (1 << c), c, time + dist[position][c])) {
        clear = true;
      }
    }
  }
  return clear;
}

int main() {
  std::ios_base::sync_with_stdio(false);
  while (cin >> n >> hx >> hy >> dx >> dy, n | hx | hy | dx | dy) {
    cristals.clear();
    REP(i, n) {
      int x, y;
      cin >> x >> y;
      cristals.PB(P(x, y));
    }
    cristals.PB(P(hx, hy));

    dist = VVD(cristals.size(), VD(cristals.size(), INF));
    REP(i, cristals.size()) {
      REP(j, cristals.size()) {
        dist[i][j] = sqrt(norm(cristals[i] - cristals[j]));
      }
    }

    limits = VD(n);
    REP(i, n) { limits[i] = sqrt(norm(cristals[i] - P(dx, dy))); }
    limits.PB(INF);

    if (get_cristal(0, cristals.size() - 1, 0)) {
      cout << "YES" << endl;
    } else {
      cout << "NO" << endl;
    }
  }
}

// vim: foldmethod=marker

Error: TLE

Fixed submission:

#define DEBUG_ON
#define CONDITION true
using namespace std; /*{{{*/

#include <algorithm>
#include <cassert>
#include <cctype>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <sys/time.h>
#include <vector>

#define INF (1e9)
static const double PI = acos(-1.0);
static const double EPS = 1e-10;

typedef long long int LL;
typedef unsigned long long int ULL;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<double> VD;
typedef vector<VD> VVD;
typedef vector<bool> VB;
typedef vector<VB> VVB;
typedef vector<char> VC;
typedef vector<VC> VVC;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef complex<double> P;

#define FOR(i, b, e) for (typeof(e) i = (b); i != (e); i < (e) ? ++i : --i)
#define REP(i, n) FOR(i, 0, n)

#define IFC(c)                                                                 \\
  if (c)                                                                       \\
    continue;
#define IFB(c)                                                                 \\
  if (c)                                                                       \\
    break;
#define IFR(c, r)                                                              \\
  if (c)                                                                       \\
    return r;

#define OPOVER(_op, _type) inline bool operator _op(const _type &t) const

#define arrsz(a) (sizeof(a) / sizeof(a[0]))

#define F first
#define S second
#define MP(a, b) make_pair(a, b)

#define SZ(a) ((LL)a.size())
#define PB(e) push_back(e)
#define SORT(v) sort((v).begin(), (v).end())
#define RSORT(v) sort((v).rbegin(), (v).rend())

#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define EACH(c, it)                                                            \\
  for (__typeof((c).begin()) it = (c).begin(); it != (c).end(); ++it)
#define EXIST(s, e) ((s).find(e) != (s).end())

#define BIT(n) (1ULL << (n))
#define BITOF(n, m) ((ULL)(n) >> (m)&1)

#define RANGE(a, b, c) ((a) <= (b) && (b) <= (c))

#define PQ priority_queue
#define SC static_cast

#ifdef DEBUG_ON
#define dprt(fmt, ...)                                                         \\
  if (CONDITION)                                                               \\
  fprintf(stderr, fmt, ##__VA_ARGS__)
#define darr(a)                                                                \\
  if (CONDITION)                                                               \\
    copy((a), (a) + arrsz(a), ostream_iterator<int>(cerr, " "));               \\
  cerr << endl
#define darr_range(a, f, t)                                                    \\
  if (CONDITION)                                                               \\
    copy((a) + (f), (a) + (t), ostream_iterator<int>(cerr, " "));              \\
  cerr << endl
#define dvec(v)                                                                \\
  if (CONDITION)                                                               \\
    copy(ALL(v), ostream_iterator<int>(cerr, " "));                            \\
  cerr << endl
#define darr2(a, n, m)                                                         \\
  if (CONDITION)                                                               \\
    FOR(i, 0, (n)) { darr_range((a)[i], 0, (m)); }
#define dvec2(v)                                                               \\
  if (CONDITION)                                                               \\
    FOR(i, 0, SZ(v)) { dvec((v)[i]); }
#define WAIT()                                                                 \\
  if (CONDITION) {                                                             \\
    string _wait_;                                                             \\
    cerr << "(hit return to continue)" << endl;                                \\
    getline(cin, _wait_);                                                      \\
  }
#define dump(x)                                                                \\
  if (CONDITION)                                                               \\
    cerr << " [L" << __LINE__ << "] " << #x << " = " << (x) << endl;
#define dumpf()                                                                \\
  if (CONDITION)                                                               \\
    cerr << __PRETTY_FUNCTION__ << endl;
#define dumpv(x)                                                               \\
  if (CONDITION)                                                               \\
    cerr << " [L:" << __LINE__ << "] " << #x << " = ";                         \\
  REP(q, (x).size()) cerr << (x)[q] << " ";                                    \\
  cerr << endl;
#define where()                                                                \\
  if (CONDITION)                                                               \\
    cerr << __FILE__ << ": " << __PRETTY_FUNCTION__ << " [L: " << __LINE__     \\
         << "]" << endl;
#define show_bits(b, s)                                                        \\
  if (CONDITION) {                                                             \\
    REP(i, s) {                                                                \\
      cerr << BITOF(b, s - 1 - i);                                             \\
      if (i % 4 == 3)                                                          \\
        cerr << ' ';                                                           \\
    }                                                                          \\
    cerr << endl;                                                              \\
  }
#else
#define cerr                                                                   \\
  if (0)                                                                       \\
  cerr
#define dprt(fmt, ...)
#define darr(a)
#define darr_range(a, f, t)
#define dvec(v)
#define darr2(a, n, m)
#define dvec2(v)
#define WAIT()
#define dump(x)
#define dumpf()
#define dumpv(x)
#define where()
#define show_bits(b, s)
#endif

/* Inline functions */
inline int onbits_count(ULL b) {
  int c = 0;
  while (b != 0) {
    c += (b & 1);
    b >>= 1;
  }
  return c;
}
inline int bits_count(ULL b) {
  int c = 0;
  while (b != 0) {
    ++c;
    b >>= 1;
  }
  return c;
}
inline int toInt(string s) {
  int v;
  istringstream sin(s);
  sin >> v;
  return v;
}
template <class T> inline string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}
inline double now() {
  struct timeval tv;
  gettimeofday(&tv, NULL);
  return (static_cast<double>(tv.tv_sec) +
          static_cast<double>(tv.tv_usec) * 1e-6);
}
inline VS split(string s, char delimiter) {
  VS v;
  string t;
  REP(i, s.length()) {
    if (s[i] == delimiter)
      v.PB(t), t = "";
    else
      t += s[i];
  }
  v.PB(t);
  return v;
}

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

/* Frequent stuffs */
int n_dir = 4;
enum direction { UP, RIGHT, DOWN, LEFT };
// int n_dir = 8;
// int dx[] = {0, 1, 1, 1, 0, -1, -1, -1}, dy[] = {-1, -1, 0, 1, 1, 1, 0, -1};
// enum direction {
// UP, UPRIGHT, RIGHT, DOWNRIGHT, DOWN, DOWNLEFT, LEFT, UPLEFT
// }
#define FORDIR(d) REP(d, n_dir)

/*}}}*/

int n, hx, hy, dx, dy;
VVD dist;
vector<P> cristals;
VD limits;

bool get_cristal(int status, int position, double time) {
  if (time > limits[position] - EPS) {
    return false;
  }
  if (status == (1 << n) - 1) {
    return true;
  }
  bool clear = false;
  REP(c, n) {
    if ((status & (1 << c)) == 0) {
      // Get c-th cristal
      if (get_cristal(status | (1 << c), c, time + dist[position][c])) {
        clear = true;
      }
    }
  }
  return clear;
}

int main() {
  std::ios_base::sync_with_stdio(false);
  while (cin >> n >> hx >> hy >> dx >> dy, n | hx | hy | dx | dy) {
    cristals.clear();
    REP(i, n) {
      int x, y;
      cin >> x >> y;
      cristals.PB(P(x, y));
    }
    cristals.PB(P(hx, hy));

    dist = VVD(cristals.size(), VD(cristals.size(), INF));
    REP(i, cristals.size()) {
      REP(j, cristals.size()) {
        dist[i][j] = sqrt(norm(cristals[i] - cristals[j]));
      }
    }

    limits = VD(n);
    REP(i, n) { limits[i] = sqrt(norm(cristals[i] - P(dx, dy))); }
    limits.PB(INF);

    if (get_cristal(0, cristals.size() - 1, 0)) {
      cout << "YES" << endl;
    } else {
      cout << "NO" << endl;
    }
  }
}

// vim: foldmethod=marker