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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
#712939#9520. Concave HullhanyuAC ✓257ms20568kbC++204.3kb2024-11-05 17:34:152024-11-05 17:34:17

Judging History

你现在查看的是最新测评结果

  • [2024-11-05 17:34:17]
  • 评测
  • 测评结果:AC
  • 用时:257ms
  • 内存:20568kb
  • [2024-11-05 17:34:15]
  • 提交

answer

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <queue>
#include <map>
#include <set>
#include <cassert>
using namespace std;
using ll=long long;
const int maxn=2e5+5;
#define double long double
const double eps=1e-12;
const ll mod=998244353;
const int maxp=1e5+5;
int sgn(double x) {
    if(fabs(x)<eps)
        return 0;
    if(x<0) return -1;
    return 1;
}
double sqr(double x) {
    return x*x;
}
struct Point{
    double x,y;
    Point(){}
    Point(double _x,double _y) {
        x=_x;
        y=_y;
    }
    bool operator == (const Point& b) const {
        return sgn(x-b.x)==0&&sgn(y-b.y)==0;
    }
    bool operator < (const Point& b) const {
        return sgn(x-b.x)==0?sgn(y-b.y)<0:x<b.x;
    }
    Point operator - (const Point& b) const {
        return Point(x-b.x,y-b.y);
    }
    Point operator + (const Point& b) const {
        return Point(x+b.x,y+b.y);
    }
    double operator ^ (const Point& b) const {
        return x*b.y-y*b.x;
    }
    double operator * (const Point& b) const {
        return x*b.x+y*b.y;
    }
    double distance(Point b) {
        return hypot(x-b.x, y-b.y);
    }
};
struct Polygon {
    int n;
    Point p[maxp];
    struct cmp {
        Point p;
        cmp(const Point& p0) {
            p=p0;
        }
        bool operator() (const Point& aa,const Point& bb) {
            Point a=aa,b=bb;
            int d=sgn((a-p)^(b-p));
            if(d==0)
                return sgn(a.distance(p)-b.distance(p))<0;
            return d>0;
        }
    };
    void norm() {
        Point mi=p[0];
        for(int i=1;i<n;i++) mi=min(mi,p[i]);
        sort(p,p+n,cmp(mi));
    }
    void getconvex(Polygon& convex) {
        sort(p,p+n);
        convex.n=n;
        for(int i=0;i<min(n,2);i++) {
            convex.p[i]=p[i];
        }
        if(convex.n==2&&convex.p[0]==convex.p[1])
            convex.n--;
        if(n<=2) return;
        int &top=convex.n;
        top=1;
        for(int i=2;i<n;i++) {
            while (top&&sgn((convex.p[top]-p[i])^(convex.p[top-1]-p[i]))<=0) {
                top--;
            }
            convex.p[++top]=p[i];
        }
        int tmp=top;
        convex.p[++top]=p[n-2];
        for(int i=n-3;i>=0;i--) {
            while (top!=tmp&&sgn((convex.p[top]-p[i])^(convex.p[top-1]-p[i]))<=0) {
                top--;
            }
            convex.p[++top]=p[i];
        }
        if(convex.n==2&&convex.p[0]==convex.p[1])
            convex.n--;
        convex.norm();
    }
    double getarea() {
        double sum=0;
        for(int i=0;i<n;i++)
            sum+=p[i]^p[(i+1)%n];
        return fabs(sum)/2;
    }
};
double area(Point p,Point s,Point e) {
    return fabs(((p-s)^(p-e))/2);
}
void solve() {
    int n;
    cin>>n;
    Polygon poly,c;
    poly.n=n;
    for(int i=0;i<n;i++) {
        int x,y;
        cin>>x>>y;
        poly.p[i]=Point(x, y);
    }
    poly.getconvex(c);
    map<Point,int> mp;
    for(int i=0;i<c.n;i++)
        mp[c.p[i]];
    Polygon tmp,c2;
    int cnt=0;
    for(int i=0;i<poly.n;i++) {
        if(!mp.count(poly.p[i]))
            tmp.p[cnt++]=poly.p[i];
    }
    if(cnt==0) {
        cout<<"-1\n";
        return;
    }
    tmp.n=cnt;
    tmp.getconvex(c2);
    if(c2.n<=2){
        double ans=9e18;
        for(int i=0;i<c.n;i++) {
            Point s=c.p[i],e=c.p[(i+1)%c.n];
            ans=min(ans,area(c2.p[0], s, e));
            ans=min(ans,area(c2.p[c2.n-1], s, e));
        }
        assert(sgn(ans)>0);
        cout<<(ll)((c.getarea()-ans)*2+eps)<<"\n";
        return;
    }
    int p=0;
    double mn=9e18;
    for(int i=0;i<c2.n;i++) {
        double d=area(c2.p[i], c.p[0], c.p[1]);
        if(d<mn) {
            mn=d;
            p=i;
        }
    }
    double ans=9e18;
    for(int i=0;i<c.n;i++) {
        Point s=c.p[i],e=c.p[(i+1)%c.n];
        while (c2.n>1&&sgn(area(c2.p[(p+1)%c2.n], s, e)-area(c2.p[p%c2.n], s, e))<=0) {
            p++;
        }
        p%=c2.n;
        ans=min(ans,area(c2.p[p], s, e));
    }
    assert(sgn(ans)>0);
    cout<<(ll)((c.getarea()-ans)*2+eps)<<"\n";
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int t=1;
    cin>>t;
    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: 2ms
memory: 16344kb

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: 2ms
memory: 16212kb

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: 57ms
memory: 16252kb

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: 257ms
memory: 16428kb

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: 84ms
memory: 16576kb

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: 71ms
memory: 16564kb

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: 18364kb

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: 82ms
memory: 19308kb

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: 111ms
memory: 20568kb

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: 16212kb

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