Problem p01140 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;

#define pb(n) push_back(n)
#define fi first
#define se second
#define all(r) begin(r), end(r)
#define vmax(ary) *max_element(all(ary))
#define vmin(ary) *min_element(all(ary))
#define debug(x) cout << #x << ": " << x << endl
#define fcout(n) cout << fixed << setprecision((n))
#define scout(n) cout << setw(n)
#define vary(type, name, size, init) vector<type> name(size, init)
#define vvl(v, w, h, init) vector<vector<ll>> v(w, vector<ll>(h, init))
#define mp(a, b) make_pair(a, b)

#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define REP(i, a, b) for (int i = (a); i < (int)(b); ++i)
#define repi(it, array)                                                        \\
  for (auto it = array.begin(), end = array.end(); it != end; ++it)
#define repa(n, array) for (auto &n : (array))

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

template <typename T> void O(T t) { cout << t << endl; }

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  double d = 1000 * 1510;
  ll n, m, k;
  double w, b;
  while (cin >> n >> m, n + m) {
    vector<ll> x(n + 1), y(m + 1);
    k = 0;
    rep(i, n) {
      cin >> w;
      k += w;
      x[i + 1] = k;
    }
    k = 0;
    rep(i, m) {
      cin >> w;
      k += w;
      y[i + 1] = k;
    }
    map<int, int> ans;
    rep(i, n + 1) {
      rep(j, m + 1) { ans[int(y[j] - x[i])]++; }
    }
    ll cnt = 0;
    for (auto p : ans) {
      int o = p.se;
      cnt += o * (o - 1) / 2;
    }
    cout << cnt << endl;
  }
  return 0;
}

Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;

#define pb(n) push_back(n)
#define fi first
#define se second
#define all(r) begin(r), end(r)
#define vmax(ary) *max_element(all(ary))
#define vmin(ary) *min_element(all(ary))
#define debug(x) cout << #x << ": " << x << endl
#define fcout(n) cout << fixed << setprecision((n))
#define scout(n) cout << setw(n)
#define vary(type, name, size, init) vector<type> name(size, init)
#define vvl(v, w, h, init) vector<vector<ll>> v(w, vector<ll>(h, init))
#define mp(a, b) make_pair(a, b)

#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define REP(i, a, b) for (int i = (a); i < (int)(b); ++i)
#define repi(it, array)                                                        \\
  for (auto it = array.begin(), end = array.end(); it != end; ++it)
#define repa(n, array) for (auto &n : (array))

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

template <typename T> void O(T t) { cout << t << endl; }
const double EPS = 1e-8;
const double INF = 1e12;
typedef complex<double> P; //????´???°????????¢?????????????????¨?§£???
namespace std {
bool operator<(const P &a, const P &b) { // x????????????
  return real(a) != real(b) ? real(a) < real(b) : imag(a) < imag(b);
}
bool sorty(const P &a, const P &b) { // y????????????
  return imag(a) != imag(b) ? imag(a) < imag(b) : real(a) < real(b);
}
bool same(const P &a, const P &b) {
  P p = a - b;
  if (abs(real(p)) < EPS && abs(imag(p)) < EPS) {
    return true;
  }
  return false;
}
} // namespace std
double cross(const P &a, const P &b) { //??????
  return imag(conj(a) * b);
}
double dot(const P &a, const P &b) { //??????
  return real(conj(a) * b);
}

class L { // line
public:
  vector<P> l;
  P v;
  L(){};
  L(const P &a, const P &b) {
    l.push_back(a);
    l.push_back(b);
    v = (b - a);
  }
  L(double a, double b, double c, double d) {
    l.push_back(P(a, b)), l.push_back(P(c, d));
  }
  P &operator[](const int i) { return l[i]; }
  void readL() {
    double a, b, c, d;
    cin >> a >> b >> c >> d;
    l.clear();
    l.push_back(P(a, b)), l.push_back(P(c, d));
  }
};

int ccw(P a, P b, P c) { // 3????????????????????§????????§??????????????????
  b -= a;
  c -= a;
  if (cross(b, c) > 0)
    return +1; // counter clockwise
  if (cross(b, c) < 0)
    return -1; // clockwise
  if (dot(b, c) < 0)
    return +2; // c--a--b on line
  if (norm(b) < norm(c))
    return -2; // a--b--c on line
  return 0;    // a--c--b on line
}
bool intersectLL(L &l, L &m) {
  return abs(cross(l[1] - l[0], m[1] - m[0])) > EPS || // non-parallel
         abs(cross(l[1] - l[0], m[0] - l[0])) < EPS;   // same line
}
bool intersectLS(L &l, L &s) {
  return cross(l[1] - l[0], s[0] - l[0]) * // s[0] is left of l
             cross(l[1] - l[0], s[1] - l[0]) <
         EPS; // s[1] is right of l
}
bool intersectLP(L &l, P &p) { return abs(cross(l[1] - p, l[0] - p)) < EPS; }
bool intersectSS(L &s, L &t) {
  return ccw(s[0], s[1], t[0]) * ccw(s[0], s[1], t[1]) <= 0 &&
         ccw(t[0], t[1], s[0]) * ccw(t[0], t[1], s[1]) <= 0;
}
bool intersectSP(L &s, P &p) {
  return abs(s[0] - p) + abs(s[1] - p) - abs(s[1] - s[0]) <
         EPS; // triangle inequality
}
// L & P intersection
P projection(L &l, P &p) {
  double t = dot(p - l[0], l[0] - l[1]) / norm(l[0] - l[1]);
  return l[0] + t * (l[0] - l[1]);
}
// L????????????P???????°????
P reflection(L &l, P &p) { return p + 2.0 * (projection(l, p) - p); }
P crosspointSS(L &l1, L &l2) {
  double d1 = abs(cross(l2.v, l1[0] - l2[0])); // l1.a - l2.b???
  double d2 = abs(cross(l2.v, l1[1] - l2[0]));
  double t = d1 / (d1 + d2);
  return l1[0] + t * l1.v;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  double d = 1000 * 1510;
  ll n, m, k;
  double w, b;
  while (cin >> n >> m, n + m) {
    P a, b;
    vector<P> ps((n + 1) * (m + 1));
    vector<L> x(n + 1), y(m + 1);
    y[0] = L(P(-1, 0), P(d, 0));
    x[0] = L(P(0, -1), P(0, d));
    k = 0;
    rep(i, n) {
      cin >> w;
      k += w;
      a = P(k, -1), b = P(k, d);
      x[i + 1] = L(a, b);
    }
    k = 0;
    rep(i, m) {
      cin >> w;
      k += w;
      a = P(-1, k), b = P(d, k);
      y[i + 1] = L(a, b);
    }
    rep(i, n + 1) {
      rep(j, m + 1) { ps[i * (m + 1) + j] = (crosspointSS(x[i], y[j])); }
    }
    sort(all(ps));
    ll cnt = 0, fc = 0;
    vector<bool> f(ps.size(), true);
    rep(i, ps.size()) {
      if (!f[i])
        continue;
      f[i] = false;
      ++fc;
      P p = ps[i] + P(d, d);
      L l(ps[i], p);
      ll c = 1;
      REP(j, i + 1, ps.size()) {
        if (intersectLP(l, ps[j])) {
          f[j] = false;
          ++fc;
          ++c;
        }
      }
      cnt += c * (c - 1) / 2;
      if (fc >= ps.size())
        break;
    }
    cout << cnt << endl;
  }
  return 0;
}