#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define f first
#define s second
const int maxn = 1 << 17;
struct line {
pii a, b;
};
int n;
pair<pii, int> p[maxn];
pii org[maxn];
int arr[maxn];
vector<line> add[maxn];
vector<line> rem[maxn];
vector<pair<pii,int> > query[maxn];
vector<int> ans;
ll ccw(pii a, pii b, pii c) {
return ll(a.f) * (b.s - c.s) + ll(b.f) * (c.s - a.s) + ll(c.f) * (a.s - b.s);
}
bool comp(pair<pii, int> a, pair<pii, int> b) {
ll c = ccw(pii(0, 0), a.f, b.f);
if(c == 0)
return a.s < b.s;
return c > 0;
}
bool operator==(line x, line y) {
return x.a == y.a && x.b == y.b;
}
bool operator<(line x, line y) {
if(x == y)
return false;
if(x.a == y.a)
return x.b < y.b;
if(x.a == y.b)
return x.b < y.a;
if(x.b == y.a)
return x.a < y.b;
if(x.b == y.b)
return x.a < y.a;
ll xa, xb, ya, yb;
xa = ccw(x.a, x.b, y.a);
xb = ccw(x.a, x.b, y.b);
ya = ccw(y.a, y.b, x.a);
yb = ccw(y.a, y.b, x.b);
// cout << "values: " << xa << " " << xb << " " << ya << " " << yb << endl;
bool ret = false;
if((xa > 0) == (xb > 0) || !xa || !xb) {
if(!xa)
ret = xb < 0;
else
ret = xa < 0;
} else if ((ya > 0) == (yb > 0) || !ya || !yb) {
if(!ya)
ret = yb > 0;
else
ret = ya > 0;
} else {
// cout << x.a.f << "," << x.a.s << "-" << x.b.f << "," << x.b.s << " " << y.a.f << "," << y.a.s << "-" << y.b.f << "," << y.b.s << endl;
assert(false);
}
// cout << ret << " " << xb << ": " << x.a.f << "," << x.a.s << "-" << x.b.f << "," << x.b.s << " " << y.a.f << "," << y.a.s << "-" << y.b.f << "," << y.b.s << endl;
// cout << endl;
return ret;
}
void sweep() {
set<line> st;
for(int t = 1; t <= n; t++) {
for(const line &i : add[t]) {
st.insert(i);
}
// assert(!st.empty());
line f = *st.begin();
for(const pair<pii, int> &i : query[t]) {
if(ccw(f.a, f.b, i.f) == 0) {
ans.push_back(i.s);
}
}
// cout << "trebam izbrisat: ";
// for(const line &i : rem[t]) {
// cout << i.a.f << "," << i.a.s << "-" << i.b.f << "," << i.b.s << " ";
// }
// cout << endl;
for(const line &i : rem[t]) {
// cout<<(i < i)<<endl;
auto it = st.find(i);
assert(it != st.end());
// if(it != st.end())
st.erase(it);
}
// cout << "success ";
// cout << t << ": ";
// for(line i : st) {
// cout << i.a.f << "," << i.a.s << "-" << i.b.f << "," << i.b.s << " ";
// }
// cout << endl;
}
}
void add_edge(int i, int j, int x, int y) {
if(i < j) {
add[i].push_back(line{org[x], org[y]});
rem[j].push_back(line{org[x], org[y]});
} else {
add[j].push_back(line{org[y], org[x]});
rem[i].push_back(line{org[y], org[x]});
}
}
void compress() {
sort(p, p + n, comp);
for(int i = 0, k = 0; i < n; i++) {
if(i == 0 || ccw(pii(0, 0), p[i].f, p[i - 1].f))
k++;
arr[p[i].s] = k;
query[k].push_back(p[i]);
}
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
// while(true) {
// int a, b, c, d;
// cin >> a >> b >> c >> d;
// line x{pii(a, b), pii(c, d)};
// int aa, bb, cc, dd;
// cin >> aa >> bb >> cc >> dd;
// line y{pii(aa, bb), pii(cc, dd)};
// cout << (x < y) << endl;
// }
cin >> n;
for(int i = 0; i < n; i++) {
pii tmp;
cin >> tmp.f >> tmp.s;
p[i].f = tmp;
p[i].s = i;
org[i] = p[i].f;
}
compress();
// for(int i = 0; i < n; i++) {
// cout << arr[i] << " ";
// }
// cout << endl;
for(int i = 0; i < n - 1; i++)
add_edge(arr[i], arr[i + 1], i, i + 1);
add_edge(arr[n - 1], arr[0], n - 1, 0);
// for(int i = 1; i <= n; i++) {
// cout << i << ": ";
// for(line j : add[i]) {
// cout << j.a.f << "," << j.a.s << "-" << j.b.f << "," << j.b.s << " ";
// }
// cout << endl;
// }
// cout << endl;
sweep();
cout << ans.size() << endl;
sort(ans.begin(), ans.end());
for(int i : ans) {
cout << i + 1 << " ";
}
cout << endl;
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
9720 KB |
Output isn't correct |
| 2 |
Correct |
10 ms |
9720 KB |
Output is correct |
| 3 |
Correct |
11 ms |
10152 KB |
Output is correct |
| 4 |
Correct |
13 ms |
10484 KB |
Output is correct |
| 5 |
Runtime error |
25 ms |
21512 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 6 |
Runtime error |
26 ms |
21512 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 7 |
Runtime error |
33 ms |
23600 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 8 |
Runtime error |
28 ms |
23600 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 9 |
Incorrect |
20 ms |
23600 KB |
Output isn't correct |
| 10 |
Runtime error |
26 ms |
23600 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 11 |
Runtime error |
27 ms |
23600 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 12 |
Correct |
28 ms |
23600 KB |
Output is correct |
| 13 |
Runtime error |
58 ms |
26180 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 14 |
Correct |
50 ms |
27088 KB |
Output is correct |
| 15 |
Correct |
59 ms |
28240 KB |
Output is correct |
| 16 |
Execution timed out |
109 ms |
33744 KB |
Time limit exceeded |
| 17 |
Runtime error |
149 ms |
33792 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 18 |
Runtime error |
51 ms |
33792 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 19 |
Runtime error |
51 ms |
33792 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 20 |
Runtime error |
160 ms |
33792 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
