verify/geometry/AOJ_CGL_1_C.test.cpp

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• Last update: 2026-08-11 23:01:09+09:00
• Problem: https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_1_C

Depends on

• 二次元幾何の基本要素 (geometry/geometry-base.hpp)
• template/debug.hpp
• template/inout.hpp
• template/macro.hpp
• template/template.hpp
• template/util.hpp

Code

#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_1_C"

#include "template/template.hpp"
#include "geometry/geometry-base.hpp"

int main() {
  Point a, b;
  in(a, b);
  int q;
  in(q);
  const array<string, 5> ans = {"ONLINE_FRONT", "CLOCKWISE", "ON_SEGMENT",
                                "COUNTER_CLOCKWISE", "ONLINE_BACK"};
  while (q--) {
    Point c;
    in(c);
    out(ans[ccw(a, b, c) + 2]);
  }
}

#line 1 "verify/geometry/AOJ_CGL_1_C.test.cpp"
#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_1_C"

#line 2 "template/template.hpp"
#include <bits/stdc++.h>
using namespace std;

#line 2 "template/macro.hpp"
#define rep(i, a, b) for (int i = (a); i < (int)(b); i++)
#define rrep(i, a, b) for (int i = (int)(b) - 1; i >= (a); i--)
#define ALL(v) (v).begin(), (v).end()
#define UNIQUE(v) sort(ALL(v)), (v).erase(unique(ALL(v)), (v).end())
#define SZ(v) (int)v.size()
#define MIN(v) *min_element(ALL(v))
#define MAX(v) *max_element(ALL(v))
#define LB(v, x) int(lower_bound(ALL(v), (x)) - (v).begin())
#define UB(v, x) int(upper_bound(ALL(v), (x)) - (v).begin())
#define YN(b) cout << ((b) ? "YES" : "NO") << "\n";
#define Yn(b) cout << ((b) ? "Yes" : "No") << "\n";
#define yn(b) cout << ((b) ? "yes" : "no") << "\n";
#line 6 "template/template.hpp"

#line 2 "template/util.hpp"
using uint = unsigned int;
using ll = long long int;
using ull = unsigned long long;
using i128 = __int128_t;
using u128 = __uint128_t;
template <class T>
using priority_queue_asc = priority_queue<T, vector<T>, greater<T>>;

template <class T, class S = T>
S SUM(const vector<T>& a) {
  return accumulate(ALL(a), S(0));
}
template <class T1, class T2>
inline bool chmin(T1& a, T2 b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T1, class T2>
inline bool chmax(T1& a, T2 b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T1, class T2>
inline bool chmin_opt(optional<T1>& a, T2 b) {
  if (!a || a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T1, class T2>
inline bool chmax_opt(optional<T1>& a, T2 b) {
  if (!a || a < b) {
    a = b;
    return true;
  }
  return false;
}

template <class T>
int popcnt(T x) {
  return __builtin_popcountll(x);
}
template <class T>
int topbit(T x) {
  return (x == 0 ? -1 : 63 - __builtin_clzll(x));
}
template <class T>
int lowbit(T x) {
  return (x == 0 ? -1 : __builtin_ctzll(x));
}
#line 8 "template/template.hpp"

#line 2 "template/inout.hpp"
struct Fast {
  Fast() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(15);
  }
} fast;

ostream& operator<<(ostream& os, __uint128_t x) {
  char buf[40];
  size_t k = 0;
  while (x > 0) buf[k++] = (char)(x % 10 + '0'), x /= 10;
  if (k == 0) buf[k++] = '0';
  while (k) os << buf[--k];
  return os;
}
ostream& operator<<(ostream& os, __int128_t x) {
  return x < 0 ? (os << '-' << (__uint128_t)(-x)) : (os << (__uint128_t)x);
}
template <class T, size_t N>
ostream& operator<<(ostream& os, const array<T, N>& a);
template <class T1, class T2>
istream& operator>>(istream& is, pair<T1, T2>& p) {
  return is >> p.first >> p.second;
}
template <class T1, class T2>
ostream& operator<<(ostream& os, const pair<T1, T2>& p) {
  return os << p.first << " " << p.second;
}
template <class T>
istream& operator>>(istream& is, vector<T>& a) {
  for (auto& v : a) is >> v;
  return is;
}
template <class T>
ostream& operator<<(ostream& os, const vector<T>& a) {
  for (auto it = a.begin(); it != a.end();) {
    os << *it;
    if (++it != a.end()) os << " ";
  }
  return os;
}
template <class T, size_t N>
ostream& operator<<(ostream& os, const array<T, N>& a) {
  for (auto it = a.begin(); it != a.end();) {
    os << *it;
    if (++it != a.end()) os << " ";
  }
  return os;
}
template <class T>
ostream& operator<<(ostream& os, const set<T>& st) {
  os << "{";
  for (auto it = st.begin(); it != st.end();) {
    os << *it;
    if (++it != st.end()) os << ",";
  }
  os << "}";
  return os;
}
template <class T1, class T2>
ostream& operator<<(ostream& os, const map<T1, T2>& mp) {
  os << "{";
  for (auto it = mp.begin(); it != mp.end();) {
    os << it->first << ":" << it->second;
    if (++it != mp.end()) os << ",";
  }
  os << "}";
  return os;
}

void in() {}
template <typename T, class... U>
void in(T& t, U&... u) {
  cin >> t;
  in(u...);
}
template <class... T>
void in_zip(int n, T&... t) {
  assert(n >= 0 && ((size(t) >= static_cast<size_t>(n)) && ...));
  for (int i = 0; i < n; i++) in(t[i]...);
}
void out() { cout << "\n"; }
template <typename T, class... U, char sep = ' '>
void out(const T& t, const U&... u) {
  cout << t;
  if (sizeof...(u)) cout << sep;
  out(u...);
}
template <class T, class U>
void out_opt(const optional<T>& opt, const U& fallback, ostream& os = cout) {
  if (opt.has_value())
    os << opt.value();
  else
    os << fallback;
  os << "\n";
}
template <class T, class U>
void out_opt(const vector<optional<T>>& vec, const U& fallback, ostream& os = cout) {
  for (auto it = vec.begin(); it != vec.end();) {
    if ((*it).has_value())
      os << (*it).value();
    else
      os << fallback;
    if (++it != vec.end()) os << " ";
  }
  os << "\n";
}

namespace IO {
template <class T, class... U>
T read(U&&... u) {
  T t = T(forward<U>(u)...);
  in(t);
  return t;
}
namespace Graph {
vector<vector<int>> unweighted(int n, int m, bool directed = false, int offset = 1) {
  vector<vector<int>> g(n);
  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    u -= offset, v -= offset;
    g[u].push_back(v);
    if (!directed) g[v].push_back(u);
  }
  return g;
}
template <class T>
vector<vector<pair<int, T>>> weighted(int n, int m, bool directed = false, int offset = 1) {
  vector<vector<pair<int, T>>> g(n);
  for (int i = 0; i < m; i++) {
    int u, v;
    T w;
    cin >> u >> v >> w;
    u -= offset, v -= offset;
    g[u].push_back({v, w});
    if (!directed) g[v].push_back({u, w});
  }
  return g;
}
}  // namespace Graph
namespace Tree {
vector<vector<int>> unweighted(int n, bool directed = false, int offset = 1) {
  return Graph::unweighted(n, n - 1, directed, offset);
}
template <class T>
vector<vector<pair<int, T>>> weighted(int n, bool directed = false, int offset = 1) {
  return Graph::weighted<T>(n, n - 1, directed, offset);
}
vector<vector<int>> rooted(int n, bool to_root = true, bool to_leaf = true, int offset = 1) {
  vector<vector<int>> g(n);
  for (int i = 1; i < n; i++) {
    int p;
    cin >> p;
    p -= offset;
    if (to_root) g[i].push_back(p);
    if (to_leaf) g[p].push_back(i);
  }
  return g;
}
}  // namespace Tree
}  // namespace IO
#line 10 "template/template.hpp"

#line 2 "template/debug.hpp"
#ifdef LOCAL
#define debug 1
#define show(...) _show(0, #__VA_ARGS__, __VA_ARGS__)
#else
#define debug 0
#define show(...) true
#endif
template <class T>
void _show(int, T) {
  cerr << '\n';
}
template <class T1, class T2, class... T3>
void _show(int i, const T1& a, const T2& b, const T3&... c) {
  for (; a[i] != ',' && a[i] != '\0'; i++) cerr << a[i];
  cerr << ":" << b << " ";
  _show(i + 1, a, c...);
}
#line 2 "geometry/geometry-base.hpp"

#line 4 "geometry/geometry-base.hpp"

using Real = long double;
constexpr Real EPS = 1e-10;
constexpr Real PI = 3.141592653589793238462643383279L;
bool equals(Real x, Real y) { return fabs(x - y) < EPS; }
int sign(Real a) { return equals(a, 0) ? 0 : (a > 0 ? 1 : -1); }

template <class R>
struct PointBase {
  using P = PointBase;
  R x, y;
  PointBase() : x(0), y(0) {}
  PointBase(R _x, R _y) : x(_x), y(_y) {}
  template <typename T, typename U>
  PointBase(const pair<T, U>& p) : x(p.first), y(p.second) {}

  P operator+(const P& r) const { return P{x + r.x, y + r.y}; }
  P operator-(const P& r) const { return P{x - r.x, y - r.y}; }
  P operator-() const { return P{-x, -y}; }
  P operator*(R r) const { return P{x * r, y * r}; }
  P operator/(R r) const { return P{x / r, y / r}; }

  P& operator+=(const P& r) { return (*this) = (*this) + r; }
  P& operator-=(const P& r) { return (*this) = (*this) - r; }
  P& operator*=(R r) { return (*this) = (*this) * r; }
  P& operator/=(R r) { return (*this) = (*this) / r; }

  bool operator<(const P& r) const { return x != r.x ? x < r.x : y < r.y; }
  bool operator==(const P& r) const { return x == r.x and y == r.y; }
  bool operator!=(const P& r) const { return !((*this) == r); }

  P rotate(R rad) const {
    return {x * cos(rad) - y * sin(rad), x * sin(rad) + y * cos(rad)};
  }
  P rotate90() const { return {-y, x}; }

  R real() const { return x; }
  R imag() const { return y; }

  friend P operator*(R r, const P& p) { return p * r; }
  friend R real(const P& p) { return p.x; }
  friend R imag(const P& p) { return p.y; }
  friend R dot(const P& l, const P& r) { return l.x * r.x + l.y * r.y; }
  friend R cross(const P& l, const P& r) { return l.x * r.y - l.y * r.x; }
  friend R abs(const P& p) { return sqrt(p.x * p.x + p.y * p.y); }
  friend R norm(const P& p) { return p.x * p.x + p.y * p.y; }
  friend R arg(const P& p) { return atan2(p.y, p.x); }

  friend istream& operator>>(istream& is, P& p) {
    R a, b;
    is >> a >> b;
    p = P{a, b};
    return is;
  }
  friend ostream& operator<<(ostream& os, const P& p) {
    return os << p.x << " " << p.y;
  }
};
using Point = PointBase<Real>;
using Points = vector<Point>;

// relative position of c from a->b
int ccw(const Point& a, const Point& b, const Point& c) {
  Point x = b - a, y = c - a;
  if (cross(x, y) > EPS) return +1;        // counter-clockwise
  if (cross(x, y) < -EPS) return -1;       // clockwise
  if (dot(x, y) < -EPS) return +2;         // collinear in the order c-a-b
  if (norm(x) + EPS < norm(y)) return -2;  // collinear in the order a-b-c
  return 0;                                // collinear in the order a-c-b
}

/**
 * @brief 二次元幾何の基本要素
 * @docs docs/geometry/geometry-base.md
 */
#line 5 "verify/geometry/AOJ_CGL_1_C.test.cpp"

int main() {
  Point a, b;
  in(a, b);
  int q;
  in(q);
  const array<string, 5> ans = {"ONLINE_FRONT", "CLOCKWISE", "ON_SEGMENT",
                                "COUNTER_CLOCKWISE", "ONLINE_BACK"};
  while (q--) {
    Point c;
    in(c);
    out(ans[ccw(a, b, c) + 2]);
  }
}

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