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QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#743663 | #9520. Concave Hull | gjlccc | WA | 59ms | 22588kb | C++20 | 3.1kb | 2024-11-13 19:44:33 | 2024-11-13 19:44:38 |
Judging History
answer
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll N = 2e5 + 10;
ll n, m;
struct Point {
ll x, y, idx;
bool operator<(const Point &b) const { return x == b.x ? y < b.y : x < b.x; }
friend Point operator-(Point a, Point b) { return {a.x - b.x, a.y - b.y}; }
};
ll vis[N];
ll cross(Point a, Point b) { return a.x * b.y - a.y * b.x; }
ll cross(Point a, Point b, Point c) { return cross(b - a, c - a); }
ll dot(Point a, Point b) { return a.x * b.x + a.y * b.y; }
// Point operator-(Point a, Point b) { return {a.x - b.x, a.y - b.y}; }
// Point operator+(Point a, Point b) { return {a.x + b.x, a.y + b.y}; }
// Point operator*(Point a, ll b) { return {a.x * b, a.y * b}; }
// Point operator/(Point a, ll b) { return {a.x / b, a.y / b}; }
// ll dis(Point a) { return a.x * a.x + a.y * a.y; }
// ll dis(Point a, Point b) { return dis(a - b); }
vector<Point> a1, con1, con2, a2;
vector<Point> get_hull(vector<Point> &a) {
ll n = a.size();
if (n <= 2) {
return a;
}
vector<Point> ans(n * 2);
sort(a.begin(), a.end());
ll now = -1;
for (ll i = 0; i < n; i++) {
while (now > 0 && cross(a[i], ans[now], ans[now - 1]) <= 0) {
now--;
}
ans[++now] = a[i];
}
ll pre = now;
for (ll i = n - 2; i >= 0; i--) {
while (now > pre && cross(a[i], ans[now], ans[now - 1]) <= 0) {
now--;
}
ans[++now] = a[i];
}
ans.resize(now);
return ans;
}
void solve() {
ll n;
a1.clear();
a2.clear();
con1.clear();
con2.clear();
cin >> n;
for (ll i = 1; i <= n; i++) vis[i] = 0;
for (ll i = 1; i <= n; i++) {
ll x, y;
cin >> x >> y;
a1.emplace_back((Point){x, y, i});
}
con1 = get_hull(a1);
for (auto aaa : con1) {
vis[aaa.idx] = 1;
}
if (con1.size() == n) {
cout << -1 << "\n";
return;
}
for (auto aaa : a1) {
if (vis[aaa.idx] == 0) {
a2.push_back(aaa);
}
}
// for (auto aaa : con1) {
// cout << aaa.x << " " << aaa.y << endl;
// }
// cout << "\n";
reverse(con1.begin(), con1.end());
con2 = get_hull(a2);
reverse(con2.begin(), con2.end());
// for (auto aaa : con1) {
// cout << aaa.x << " " << aaa.y << endl;
// }
// cout << "\n";
ll ans = 0;
ll l = 0, r = 0;
ll len1 = con1.size();
ll len2 = con2.size();
ll minn = 1e18;
for (ll j = 0; j < len2; j++) {
if (cross(con1[0], con1[1], con2[j]) < minn) {
minn = cross(con1[0], con1[1], con2[j]);
r = j;
}
}
for (ll i = 0; i < len1; i++) {
ans = ans + cross(con1[i], con1[(i + 1) % len1]);
}
ans = abs(ans);
ll tmp = 1e18;
tmp = minn;
for (ll i = 0; i < len1; i++) {
while (cross(con1[i], con1[(i + 1) % len1], con2[(r + 1) % len2]) <
cross(con1[i], con1[(i + 1) % len1], con2[r])) {
r = (r + 1) % len2;
}
tmp = min(tmp, abs(cross(con1[i], con1[(i + 1) % len1], con2[r])));
}
cout << ans - tmp << "\n";
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
ll t = 1;
cin >> t;
while (t--) solve();
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3656kb
input:
2 6 -2 0 1 -2 5 2 0 4 1 2 3 1 4 0 0 1 0 0 1 1 1
output:
40 -1
result:
ok 2 lines
Test #2:
score: 0
Accepted
time: 1ms
memory: 3604kb
input:
10 243 -494423502 -591557038 -493438474 -648991734 -493289308 -656152126 -491185085 -661710614 -489063449 -666925265 -464265894 -709944049 -447472922 -737242534 -415977509 -773788538 -394263365 -797285016 -382728841 -807396819 -373481975 -814685302 -368242265 -818267002 -344482838 -833805545 -279398...
output:
2178418010787347715 1826413114144932145 1651687576234220014 1883871859778998985 2119126281997959892 894016174881844630 2271191316922158910 1998643358049669416 1740474221286618711 1168195646932543192
result:
ok 10 lines
Test #3:
score: 0
Accepted
time: 22ms
memory: 3708kb
input:
1000 125 64661186 -13143076 302828013 -185438065 -418713797 -191594241 430218126 -397441626 354327250 -836704374 149668812 -598584998 311305970 66790541 199720625 -592356787 468137 -584752683 258775829 96211747 -358669612 -134890109 -129221188 -998432368 -277309896 -140056561 356901185 420557649 -51...
output:
1986320445246155278 1900093336073022078 1612088392301142476 2012259136539173407 1819942017252118749 1772230185841892196 1164835025329039520 1527446155241140517 1807368432185303666 1236918659444944569 1306839249967484778 1984123720246784099 1868728080720036006 667458140583450322 2127932992585026491 4...
result:
ok 1000 lines
Test #4:
score: 0
Accepted
time: 28ms
memory: 3652kb
input:
10000 9 484630042 51929469 -40468396 -517784096 98214104 -103353239 629244333 -475172587 106398764 153884485 49211709 -44865749 1 10 166321833 -247717657 406208245 668933360 13 548702216 -631976459 37150086 -292461024 707804811 -486185860 239775286 -903166050 10096571 -541890068 686103484 558731937 ...
output:
950319193795831919 1661025342421008544 1285164852091455548 1159924751776806668 1206071151805176722 794021230296144371 699991678992587791 1133990718508584290 1486311831172661605 984875884297072200 1327767982175057345 758247019006396699 1355381234262206155 1139262078529131471 1613462877860621700 12392...
result:
ok 10000 lines
Test #5:
score: 0
Accepted
time: 48ms
memory: 5036kb
input:
100 439 471536154 -312612104 155692036 -937312180 -461624056 -357636609 236656684 -911414873 -288656914 -74788431 -465779694 -381475149 -334197401 -903065737 491513067 -447615916 337664889 -852236281 -281689379 -53519178 -159101704 -920779200 -326159514 -95396204 21868593 -994282736 488425383 -41046...
output:
1973162724053130487 2054612790507830954 1726805687754843724 1699420177872986528 2129388571309147631 2198295137903288810 1697185883164440272 1219697450095721478 2027023581922285255 1674691247127206655 1673105966817209954 2179188692918747442 2146544318743443141 2230356305133660648 1676850321902993764 ...
result:
ok 100 lines
Test #6:
score: 0
Accepted
time: 33ms
memory: 5164kb
input:
100 1362 -467257672 -466669 -467054869 -478108 -466973270 -481776 -466556983 -499770 -466329414 -508693 -466248017 -511805 -466158865 -513786 -466101273 -515035 -465927700 -518748 -465717624 -522106 -465303448 -528127 -465124548 -530726 -464649746 -536693 -464554872 -537799 -464478196 -538680 -46416...
output:
1666097696993497 1791366071767866 1806187278469532 1683419854733713 1685891971828916 1730190225081651 1787048201197565 1850308098208660 1710694884375502 1826363113637639 1816375352374659 2047431269497691 1549806516003854 1829438662895747 1678707854135065 1687423392883819 2121960009997761 16687219538...
result:
ok 100 lines
Test #7:
score: 0
Accepted
time: 18ms
memory: 12832kb
input:
2 62666 -486101704 -505730259 -486101698 -506082699 -486101689 -506111362 -486101682 -506126031 -486101528 -506293759 -486101259 -506556385 -486101196 -506613483 -486101154 -506648604 -486100935 -506831392 -486100631 -507083675 -486100470 -507199151 -486100233 -507368923 -486100193 -507397039 -48609...
output:
2178736946152219010 1825181940245096152
result:
ok 2 lines
Test #8:
score: 0
Accepted
time: 55ms
memory: 22588kb
input:
2 100000 301945097 76373292 467957663 -286424714 8245445 -597212507 -474204621 -708828667 184159460 105942538 443435905 -429212625 490658771 -382198656 82512047 -612522436 -228221388 -965890088 394789011 -145801151 -106120174 -528202395 428939626 -194437311 497429477 -527407728 365739746 -114818962 ...
output:
2502889432701099511 2267250485735988121
result:
ok 2 lines
Test #9:
score: 0
Accepted
time: 59ms
memory: 21400kb
input:
2 100000 221128057 -975244780 -618765360 -785575858 422567455 -906331476 -988680318 -150037424 -929870145 367887908 -757813541 -652471177 291995621 -956419655 -785381507 619012026 468864522 -883270094 -588416522 808557973 859345881 511394814 988105866 153775152 216931298 -976186873 467050734 8842305...
output:
6283183114882825575 6283183188903854361
result:
ok 2 lines
Test #10:
score: -100
Wrong Answer
time: 0ms
memory: 3848kb
input:
7 5 -1000000000 -1000000000 1000000000 -1000000000 1000000000 1000000000 1 0 -1 0 5 1000000000 1000000000 -1000000000 -1000000000 -2 0 -1 0 1 -1 6 1000000000 1000000000 -1000000000 -1000000000 -3 0 -1 0 0 -1 1 -1 4 -1000000000 -1000000000 1000000000 -1000000000 1000000000 1000000000 -1000000000 1000...
output:
4000000000000000000 7000000000 9000000001 -1 7000000000000000000 7999999998000000000 -1
result:
wrong answer 5th lines differ - expected: '6000000002000000000', found: '7000000000000000000'