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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 |
---|---|---|---|---|---|---|---|---|---|
#683999 | #9520. Concave Hull | ucup-team5141 | AC ✓ | 170ms | 25060kb | C++23 | 4.3kb | 2024-10-28 08:32:45 | 2024-10-30 01:34:12 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "../debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
using ll = long long;
using lf = long double;
const lf EPS = 1e-8L;
const lf E0 = 0.0L;//Keep = 0 for integer coordinates, otherwise = EPS
const lf INF = 5e9;
enum {OUT,IN,ON};
struct pt {
lf x,y;
pt(){}
pt(lf a , lf b): x(a), y(b){}
pt operator - (const pt &q ) const {
return {x - q.x , y - q.y };
}
pt operator + (const pt &q ) const {
return {x + q.x , y + q.y };
}
pt operator * (const lf &t ) const {
return {x * t , y * t };
}
pt operator / (const lf &t ) const {
return {x / t , y / t };
}
bool operator < ( const pt & q ) const {
if( fabsl( x - q.x ) > E0 ) return x < q.x;
return y < q.y;
}
void normalize() {
lf norm = hypotl( x, y );
if( fabsl( norm ) > EPS )
x /= norm, y /= norm;
}
};
pt rot90( pt p ) { return { -p.y, p.x }; }
pt rot( pt p, lf w ) {
return { cosl( w ) * p.x - sinl( w ) * p.y, sinl( w ) * p.x + cosl( w ) * p.y };
}
lf norm2 ( pt p ) { return p.x * p.x + p.y * p.y; }
lf dis2 ( pt p, pt q ) { return norm2(p-q); }
lf norm ( pt p ) { return hypotl ( p.x, p.y ); }
lf dis( pt p, pt q ) { return norm( p - q ); }
lf dot( pt p, pt q ) { return p.x * q.x + p.y * q.y; }
ll cross( pt p, pt q ) { return p.x * q.y - q.x * p.y ; }
lf orient( pt a, pt b, pt c ) { return cross( b - a, c - a ); };
lf angle( pt a, pt b){ return atan2(cross(a, b), dot(a, b)); }
lf abs(pt a) { return sqrt(a.x * a.x + a.y * a.y); }
bool in_angle( pt a, pt b, pt c, pt p ) {
//assert( fabsl( orient( a, b, c ) ) > E0 );
if( orient( a, b, c ) < -E0 )
return orient( a, b, p ) >= -E0 || orient( a, c, p ) <= E0;
return orient( a, b, p ) >= -E0 && orient( a, c, p ) <= E0;
}
struct line {
pt nv;
lf c;
line( pt _nv, lf _c ) : nv( _nv ), c( _c ) {}
line ( pt p, pt q ) {
nv = { p.y - q.y, q.x - p.x };
c = -dot( p, nv );
}
lf eval( pt p ) { return dot( nv, p ) + c; }
lf distance2( pt p ) {
return eval( p ) / norm2( nv ) * eval( p );
}
lf distance( pt p ) {
return fabsl( eval( p ) ) / norm( nv );
}
pt projection( pt p ) {
return p - nv * ( eval( p ) / norm2( nv ) );
}
};
vector< pt > convex_hull( vector< pt > v ) {
sort( v.begin(), v.end() );//remove repeated points if needed
const int n = v.size();
if( n < 3 ) return v;
vector< pt > ch( 2 * n );
int k = 0;
for( int i = 0; i < n; ++ i ) {
while( k > 1 && orient( ch[k-2], ch[k-1], v[i] ) <= E0 )
--k;
ch[k++] = v[i];
}
const int t = k;
for( int i = n - 2; i >= 0; -- i ) {
while( k > t && orient( ch[k-2], ch[k-1], v[i] ) <= E0 )
--k;
ch[k++] = v[i];
}
ch.resize( k - 1 );
return ch;
}
void Test(){
int n;
cin >> n;
vector<pt> a(n);
set<pt> st;
for(int i = 0; i < n; ++i){
int x, y;
cin >> x >> y;
a[i] = {x,y};
st.insert(a[i]);
}
vector<pt> h1 = convex_hull(a);
for(auto& i : h1){
st.erase(i);
}
a.clear();
for(auto& i : st){
a.push_back(i);
}
vector<pt> h2 = convex_hull(a);
n = h1.size();
int m = h2.size();
if( m == 0 ){
cout << -1 << '\n';
return;
}
for(int i = 0; i < 2 * n; ++i){
h1.push_back(h1[i]);
}
for(int i = 0; i < 2 * m; ++i){
h2.push_back(h2[i]);
}
line l1(h1[0],h1[1]);
lf d = 4e18;
int idx = -1;
for(int i = 0; i < m; ++i){
lf nd = l1.distance2(h2[i]);
if( d > nd ){
idx = i;
d = l1.distance2(h2[i]);
}
}
ll area = 0;
for(int i = 0; i < n; ++i){
area += cross(h1[i], h1[i + 1]);
}
ll ans = 0;
int j = idx;
for(int i = 0; i < 2 * n; ++i){
line l(h1[i],h1[i + 1]);
lf dis = l.distance2(h2[j]);
ans = max(ans, abs(area - cross(h1[i], h1[i + 1]) + cross(h1[i],h2[j]) + cross(h2[j],h1[i + 1])));
while( j < 3 * m && l.distance2(h2[j + 1]) < dis ){
++j;
dis = l.distance2(h2[j]);
ans = max(ans, abs(area - cross(h1[i], h1[i + 1]) + cross(h1[i],h2[j]) + cross(h2[j],h1[i + 1])));
}
ans = max(ans, abs(area - cross(h1[i], h1[i + 1]) + cross(h1[i],h2[j]) + cross(h2[j],h1[i + 1])));
}
cout << ans << '\n';
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
line l1(pt(0,0),pt(1,0));
int T;
cin >> T;
while(T--){
Test();
}
return 0;
}
这程序好像有点Bug,我给组数据试试?
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3576kb
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: 0ms
memory: 3912kb
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: 46ms
memory: 3720kb
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: 56ms
memory: 3816kb
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: 100ms
memory: 5512kb
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: 91ms
memory: 5364kb
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: 51ms
memory: 15908kb
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: 155ms
memory: 20956kb
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: 170ms
memory: 25060kb
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: 0
Accepted
time: 0ms
memory: 3632kb
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 6000000002000000000 7999999998000000000 -1
result:
ok 7 lines
Extra Test:
score: 0
Extra Test Passed