/*input
2 2
3 0 5 0
-2 1 2 1
2 1
-3 -2 -1 -1
-2 2 -1 1
*/
#include <bits/stdc++.h>
using namespace std;
namespace my_template {
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<vl> vll;
typedef vector<pi> vpi;
typedef vector<vpi> vpii;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
typedef vector<pd> vpd;
typedef vector<bool> vb;
typedef vector<vb> vbb;
typedef std::string str;
typedef std::vector<str> vs;
#define x first
#define y second
#define debug(...) cout<<"["<<#__VA_ARGS__<<": "<<__VA_ARGS__<<"]\n"
const ld PI = 3.14159265358979323846264338327950288419716939937510582097494L;
template<typename T>
pair<T, T> operator+(const pair<T, T> &a, const pair<T, T> &b) { return pair<T, T>(a.x + b.x, a.y + b.y); }
template<typename T>
pair<T, T> operator-(const pair<T, T> &a, const pair<T, T> &b) { return pair<T, T>(a.x - b.x, a.y - b.y); }
template<typename T>
T operator*(const pair<T, T> &a, const pair<T, T> &b) { return (a.x * b.x + a.y * b.y); }
template<typename T>
T operator^(const pair<T, T> &a, const pair<T, T> &b) { return (a.x * b.y - a.y * b.x); }
template<typename T>
void print(vector<T> vec, string name = "") {
cout << name;
for (auto u : vec)
cout << u << ' ';
cout << '\n';
}
}
using namespace my_template;
const int MOD = 1000000007;
const ll INF = std::numeric_limits<ll>::max();
const int MX = 100101;
struct beam {
pl prad;
pl dxy;
};
int N;
ll R;
ll dis(pl a, pl b) {
return (a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y);
}
pl getnth(ll n, pl a, pl dxy) {
return {a.x + dxy.x * n, a.y + dxy.y * n};
}
pl getnth(ll n, beam b) {
return getnth(n, b.prad, b.dxy);
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> N >> R;
pl og = {0, 0};
vector<beam> sk(N);
for (int i = 0; i < N; ++i)
{
ll a, b, c, d;
cin >> a >> b >> c >> d;
sk[i] = beam{{a, b}, {c - a, d - b}};
}
auto closest = [&](beam b) -> ll {
ll l = 0;
ll h = MOD;
ll m;
while (h - l > 4) {
m = (l + h) / 2;
pl n1 = getnth(m, b);
pl n2 = getnth(m + 1, b);
ll d1 = dis(n1, og);
ll d2 = dis(n2, og);
if (d1 == d2) {
return m;
} else if (d1 < d2) {
h = m;
} else {
l = m;
}
}
pl ret = getnth(l, b);
ll n = l;
ll c = dis(ret, og);
for (ll i = l + 1; i <= h; ++i)
{
pl nl = getnth(i, b);
ll nc = dis(nl, og);
if (nc < c) {
c = nc;
ret = nl;
n = i;
}
}
return n;
};
auto first = [&](beam b, ll best_dis) -> ll {
ll l = 0;
ll h = best_dis;
ll m;
while (l < h) {
m = (l + h) / 2;
pl n1 = getnth(m, b);
ll d1 = dis(n1, og);
if (d1 <= R * R) {
h = m;
} else {
l = m + 1;
}
}
return l;
};
auto last = [&](beam b, ll best_dis) -> ll {
ll l = best_dis;
ll h = MOD;
ll m;
while (l < h) {
m = (l + h + 1) / 2;
pl n1 = getnth(m, b);
ll d1 = dis(n1, og);
if (d1 <= R * R) {
l = m;
} else {
h = m - 1;
}
}
return l;
};
vector<pl> kas;
for (auto b : sk) {
ll ind = closest(b);
if (dis(getnth(ind, b), og) > R * R) continue;
ll from = first(b, ind);
ll to = last(b, ind);
kas.emplace_back(from, 1);
kas.emplace_back(to + 1, -1);
}
sort(kas.begin(), kas.end());
ll ats = 0;
ll curr = 0;
int j = 0;
while (j < (int)kas.size()) {
ll dabar = kas[j].x;
while (j < (int)kas.size() and kas[j].x == dabar) {
curr += kas[j].y;
j++;
}
ats = max(ats, curr);
}
printf("%lld\n", ats);
}
/* Look for:
* special cases (n=1?)
* overflow (ll vs int?)
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* array bounds
*/
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
364 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
364 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
364 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
364 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
364 KB |
Output is correct |
| 3 |
Incorrect |
1 ms |
364 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
