Problem p00120 (C++) — buggy submission, verdict: Time Limit Exceeded


#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <memory>
#include <string>

#include <algorithm>
#include <bitset>
#include <complex>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <vector>

using namespace std;

#ifdef _MSC_VER
#define __typeof__ decltype
#define strtok_r strtok_s
#endif

#define ITER(c) __typeof__((c).begin())
#define FOREACH(it, c) for (ITER(c) it = (c).begin(); it != (c).end(); ++it)
#define RITER(c) __typeof__((c).rbegin())
#define RFOREACH(it, c) for (RITER(c) it = (c).rbegin(); it != (c).rend(); ++it)
#define REP(i, n) REPEAT(i, 0, n)
#define RREP(i, n) RREPEAT(i, 0, n)
#define REPEAT(i, k, n) for (int i = (k); i < (k + n); ++i)
#define RREPEAT(i, k, n) for (int i = (k) + (n)-1; i >= (k); --i)
#define FROMTO(i, f, t) for (int i = f; i < t; i++)
#define ALL(c) (c).begin(), (c).end()
#define LLPOW(p1, p2) ((ll)pow((double)(p1), (int)p2))
#define ESIZEOF(A) (sizeof(A) / sizeof((A)[0]))
#define CIN_NO_SYNC                                                            \\
  do {                                                                         \\
    cin.tie(0);                                                                \\
    ios_base::sync_with_stdio(false);                                          \\
  } while (0)
#define GETSTR(p) fgets((p), sizeof(p), stdin)
#define CHOMP(p)                                                               \\
  do {                                                                         \\
    char *_q = (p) + strlen(p) - 1;                                            \\
    if (*_q == '\\n' || *_q == '\\r')                                            \\
      *_q = 0;                                                                 \\
  } while (0)
#define FILL(m, v) memset(m, v, sizeof(m))
#define mp make_pair
#define pb push_back
template <class _T> _T MAX(_T p1, _T p2) { return (p1 > p2) ? p1 : p2; }
template <class _T> _T MIN(_T p1, _T p2) { return (p1 < p2) ? p1 : p2; }
template <class _Tv> inline string join(_Tv &v, string sep = " ") {
  ostringstream s;
  FOREACH(it, v) {
    if (it != v.begin())
      s << sep;
    s << *it;
  };
  return s.str();
}

typedef long long ll;
typedef unsigned long long ull;

#define X real()
#define Y imag()
typedef double D;
typedef complex<D> P;
#define EPS (1e-9)

#ifdef _DEBUG
template <class _Tv>
inline void _prfe(const char *_n, _Tv _c, bool _p = false) {
  ITER(_c) _it = _c.begin();
  if (_p) {
    cout << _n << " = [" << endl;
    for (; _it != _c.end(); ++_it)
      cout << "    " << *_it << endl;
    cout << "]" << endl;
  } else {
    cout << _n << " = [ " << *_it++;
    for (; _it != _c.end(); ++_it)
      cout << ", " << *_it;
    cout << " ]" << endl;
  }
}
#define pf printf
#define pr(n)                                                                  \\
  do {                                                                         \\
    cout << #n " = " << (n) << endl;                                           \\
  } while (0)
#define prfe(n) _prfe(#n, n)
#define prfep(n) _prfe(#n, n, true)
#define dbgchk(n)                                                              \\
  do {                                                                         \\
    if (n)                                                                     \\
      throw;                                                                   \\
  } while (0)
#else
#define pf(...)     /* */
#define pr(...)     /* */
#define prfe(...)   /* */
#define prfep(...)  /* */
#define dbgchk(...) /* */
#endif

bool check(int b, vector<int> &v) {
  int n = v.size();
  double l = 0;
  REP(i, n) {
    if (i == 0) {
      l += v[i] * 2;
      continue;
    }
    double r2 = (v[i - 1] + v[i]) * (v[i - 1] + v[i]);
    double y2 = (v[i - 1] - v[i]) * (v[i - 1] - v[i]);
    // x^2 + y^2 = (r1+r2)^2
    double x = sqrt(r2 - y2);
    l = l - v[i - 1] + x + v[i];
  }
  pf("l = %.2f, b = %.0f\\n", l, (double)b);
  if (l <= (double)b) {
    return true;
  }
  return false;
}
void solve(int b, vector<int> &v) {
  int n = v.size();
  vector<int> u;

  REP(i, n) {
    u = v;
    swap(u[0], u[i]);
    REP(i, n - 1)
    FROMTO(j, i + 1, n) if (abs(u[i] - u[i + 1]) < abs(u[i] - u[j]))
        swap(u[i + 1], u[j]);
    prfe(u);
    if (check(b, u)) {
      cout << "OK" << endl;
      return;
    }
  }
  cout << "NA" << endl;
}

int main() {
  string s;
  while (getline(cin, s)) {
    istringstream ss(s);
    int b, n;
    vector<int> v;
    ss >> b;
    while (ss >> n)
      v.pb(n);
    solve(b, v);
  }

  return 0;
}

Error: TLE

Fixed submission:


#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <memory>
#include <string>

#include <algorithm>
#include <bitset>
#include <complex>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <vector>

using namespace std;

#ifdef _MSC_VER
#define __typeof__ decltype
#define strtok_r strtok_s
#endif

#define ITER(c) __typeof__((c).begin())
#define FOREACH(it, c) for (ITER(c) it = (c).begin(); it != (c).end(); ++it)
#define RITER(c) __typeof__((c).rbegin())
#define RFOREACH(it, c) for (RITER(c) it = (c).rbegin(); it != (c).rend(); ++it)
#define REP(i, n) REPEAT(i, 0, n)
#define RREP(i, n) RREPEAT(i, 0, n)
#define REPEAT(i, k, n) for (int i = (k); i < (k + n); ++i)
#define RREPEAT(i, k, n) for (int i = (k) + (n)-1; i >= (k); --i)
#define FROMTO(i, f, t) for (int i = f; i < t; i++)
#define ALL(c) (c).begin(), (c).end()
#define LLPOW(p1, p2) ((ll)pow((double)(p1), (int)p2))
#define ESIZEOF(A) (sizeof(A) / sizeof((A)[0]))
#define CIN_NO_SYNC                                                            \\
  do {                                                                         \\
    cin.tie(0);                                                                \\
    ios_base::sync_with_stdio(false);                                          \\
  } while (0)
#define GETSTR(p) fgets((p), sizeof(p), stdin)
#define CHOMP(p)                                                               \\
  do {                                                                         \\
    char *_q = (p) + strlen(p) - 1;                                            \\
    if (*_q == '\\n' || *_q == '\\r')                                            \\
      *_q = 0;                                                                 \\
  } while (0)
#define FILL(m, v) memset(m, v, sizeof(m))
#define mp make_pair
#define pb push_back
template <class _T> _T MAX(_T p1, _T p2) { return (p1 > p2) ? p1 : p2; }
template <class _T> _T MIN(_T p1, _T p2) { return (p1 < p2) ? p1 : p2; }
template <class _Tv> inline string join(_Tv &v, string sep = " ") {
  ostringstream s;
  FOREACH(it, v) {
    if (it != v.begin())
      s << sep;
    s << *it;
  };
  return s.str();
}

typedef long long ll;
typedef unsigned long long ull;

#define X real()
#define Y imag()
typedef double D;
typedef complex<D> P;
#define EPS (1e-9)

#ifdef _DEBUG
template <class _Tv>
inline void _prfe(const char *_n, _Tv _c, bool _p = false) {
  ITER(_c) _it = _c.begin();
  if (_p) {
    cout << _n << " = [" << endl;
    for (; _it != _c.end(); ++_it)
      cout << "    " << *_it << endl;
    cout << "]" << endl;
  } else {
    cout << _n << " = [ " << *_it++;
    for (; _it != _c.end(); ++_it)
      cout << ", " << *_it;
    cout << " ]" << endl;
  }
}
#define pf printf
#define pr(n)                                                                  \\
  do {                                                                         \\
    cout << #n " = " << (n) << endl;                                           \\
  } while (0)
#define prfe(n) _prfe(#n, n)
#define prfep(n) _prfe(#n, n, true)
#define dbgchk(n)                                                              \\
  do {                                                                         \\
    if (n)                                                                     \\
      throw;                                                                   \\
  } while (0)
#else
#define pf(...)     /* */
#define pr(...)     /* */
#define prfe(...)   /* */
#define prfep(...)  /* */
#define dbgchk(...) /* */
#endif

void solve(int b, vector<int> &v) {
  int n = v.size();
  bool f = false;
  sort(ALL(v));
  do {
    double l = 0;

    REP(i, n) {
      if (i == 0) {
        l += v[i] * 2;
        continue;
      }

      double r2 = (v[i - 1] + v[i]) * (v[i - 1] + v[i]);
      double y2 = (v[i - 1] - v[i]) * (v[i - 1] - v[i]);
      // x^2 + y^2 = (r1+r2)^2
      double x = sqrt(r2 - y2);
      l = l - v[i - 1] + x + v[i];
    }

    if (l <= (double)b) {
      pr(l);
      f = true;
      break;
    }
  } while (next_permutation(ALL(v)));

  cout << (f ? "OK" : "NA") << endl;
}

int main() {
  string s;
  while (getline(cin, s)) {
    istringstream ss(s);
    int b, n;
    vector<int> v;
    ss >> b;
    while (ss >> n)
      v.pb(n);
    solve(b, v);
  }

  return 0;
}