QOJ.ac
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 |
---|---|---|---|---|---|---|---|---|---|
#683718 | #9520. Concave Hull | HHAZ | AC ✓ | 139ms | 30196kb | C++20 | 3.7kb | 2024-10-27 22:58:34 | 2024-10-30 01:33:51 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define endl '\n'
typedef long long ll;
typedef long double ld;
#define endl '\n'
#define sz(x) (int)(x).size()
#define all(t) (t).begin(), (t).end()
#define rep(i, a, b) for (ll i = (a); i <= (b); ++i)
#define per(i, a, b) for(ll i = (a); i >= (b); --i)
#define debug(x) cout<<#x<<": "<<x<<endl
const int N=2e5+10,M=1e6+10;
const ld eps=1e-12;
#define double long double
int sgn(double x)
{
if(fabs(x)<eps) return 0;
return x>0?1:-1;
}
typedef struct point
{
double x,y;
point(double x=0,double y=0) :x(x),y(y){}
point operator - (point b) {return point(x-b.x,y-b.y);}
double operator ^ (point b) {return x*b.y-y*b.x;}
bool operator < (const point &b) const {return sgn(x-b.x)==0?sgn(y-b.y)<0:x<b.x;}
bool operator == (const point &b) const {return sgn(x-b.x)==0&&sgn(y-b.y)==0;}
}Vector;
typedef struct line
{
point s,e;
line(point s1,point e1) {s=s1,e=e1;}
}seg;
double cross(point a,point b,point c) {return (b-a)^(c-a);}
struct polygon
{
int n=0;
vector<point>p;
vector<line>l;
void add(point x){p.push_back(x),n++;}
void getline()
{
for(int i=0;i<n;i++)
l.push_back(line(p[i],p[(i+1)%n]));
}
vector<point> Andrew()
{
vector<point>s;
sort(p.begin(),p.end());
for(int i=0;i<n;i++)
{
while(s.size()>1&&cross(s[s.size()-2],s[s.size()-1],p[i])<=0) s.pop_back();
s.push_back(p[i]);
}
int t=s.size();
for(int i=n-2;i>=0;i--)
{
while(s.size()>t&&cross(s[s.size()-2],s[s.size()-1],p[i])<=0) s.pop_back();
s.push_back(p[i]);
}
if(s.size()>1) s.pop_back();
p=s,n=s.size();
return s;
}
double area()
{
double sum=0;
for(int i=0;i<n;i++) sum+=p[i]^p[(i+1)%n];
return fabs(sum)/2;
}
};
double area(line l,point p)
{
return fabs((p-l.s)^(l.e-l.s))/2;
}
void solve()
{
int n;
cin>>n;
vector<point>p;
polygon yuan;
for(int i=1;i<=n;i++)
{
ll x,y;
cin>>x>>y;
p.push_back(point(x,y));
yuan.add(p[i-1]);
}
map<pair<double,double>,int>mp;
vector<point>f=yuan.Andrew();
polygon F,G;
for(auto p:f) F.add(p),mp[{p.x,p.y}] = 1;
F.Andrew();
double ans=F.area();
// debug(ans);
for(auto u:p) if(!mp.count({u.x,u.y})) G.add(u);
G.Andrew();
F.getline();
vector<seg>l=F.l;
n=l.size();
// debug(l.size());
vector<point>np=G.p;
// for(auto u:np) debug(u.x),debug(u.y);
int m=np.size();
// debug(m);
if(m==0)
{
cout<<-1<<endl;
return;
}
int pp=0;
double minn=area(l[0],np[pp]);
for(int i=1;i<m;i++)
{
if(area(l[0],np[i])<minn)
{
minn=area(l[0],np[i]);
pp=i;
}
};
for(int pl=1;pl<n;pl++)
{
while(1)
{
if(area(l[pl],np[pp])<=area(l[pl],np[(pp+1)%m])) break;
else pp++, pp %= m;
}
// if(!area(l[pl],np[pp])) {
// debug(l[pl].e.x);
// debug(l[pl].e.y);
// debug(l[pl].s.x);
// debug(l[pl].s.y);
// debug(np[pp].x);
// debug(np[pp].y);
// debug(np.size());
// debug(pp);
// exit(0);
// }
minn=min(minn,area(l[pl],np[pp]));
}
cout<<fixed << setprecision(0)<<2*(ans-minn)<<endl;
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int T = 1;
cin >> T;
// cout.flush();
// ofstream outfile("C:\\Users\\86187\\OneDrive\\桌面\\1.txt");
// outfile << "a[1]=0;a[2]=1;";
// ll l = 1e7 + 1;
// rep(i, 3, 1e9) {
// printf("%lld\n", i);
// ll x = (i - 1) * ((a[i - 1] + a[i - 2]) % mod);
// x %= mod;
// if(i == l) {
// outfile << "a[" << i << "]=" << x << ";";
// }
// if(i == l + 1) {
// outfile << "a[" << i << "]=" << x << ";";
// l += 1e7;
// }
// }
while(T--) {
solve();
}
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: 4040kb
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: 3828kb
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: 45ms
memory: 3940kb
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: 67ms
memory: 3780kb
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: 6520kb
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: 87ms
memory: 5876kb
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: 42ms
memory: 15440kb
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: 132ms
memory: 24368kb
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: 139ms
memory: 30196kb
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: 3820kb
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