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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#715722#9520. Concave HullyxyAC ✓130ms14856kbC++173.9kb2024-11-06 13:10:582024-11-06 13:10:59

Judging History

你现在查看的是最新测评结果

  • [2024-11-06 13:10:59]
  • 评测
  • 测评结果:AC
  • 用时:130ms
  • 内存:14856kb
  • [2024-11-06 13:10:58]
  • 提交

answer

#include<bits/stdc++.h>

#define N 2000979
#define M 31
#define LL long long
#define pii pair<int, int> 
#define pll pair<LL, LL>
#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define lbd lower_bound
#define ubd upper_bound
#define IO ios :: sync_with_stdio(false), cin.tie(0)

using namespace std;

const LL INF = (LL)1E18;

int n;
template<class T = LL> 
struct Points {
    T x, y;
    Points operator + (const Points & o) const {return {x + o.x, y + o.y};}
    Points operator - (const Points & o) const {return {x - o.x, y - o.y};}
    T operator ^ (const Points & o) const {return x * o.x + y * o.y; }
    T operator * (const Points & o) const {return x * o.y - y * o.x; } 
    double len() {return sqrt(1.0 * ((*this) * (*this))); }
    T len2() {return (*this) * (*this);}
};

vector<Points<>> vec;
int stk[N];
int tp = 0;
map<array<LL, 2>, bool> rec;

template<class T = LL>
vector<Points<T>> convex(vector<Points<T>> vec) {
    sort(vec.begin(), vec.end(), [&] (const Points<> & a, const Points<> & b) -> bool {
        if (a.x == b.x) return a.y < b.y; 
        return a.x < b.x;
    });

    if (vec.size() == 1) {
        return {vec[0], vec[0]};
    }
    if (vec.size() == 2) {
        return {vec[0], vec[1], vec[0]};
    }

    vector<int> vis(vec.size(), 0);

    tp = 0; 
    stk[++ tp] = 0; 
    for (int i = 1; i < vec.size(); i ++) {
        while (tp > 1 && (vec[i] - vec[stk[tp]]) * (vec[stk[tp]] - vec[stk[tp - 1]]) >= 0) {
            vis[stk[tp]] = 0;
            tp --; 
        } 
        stk[++ tp] = i;
        vis[i] = 1;
    }

    int k = tp;
    for (int i = vec.size() - 2; i >= 0; i --) if (!vis[i]) {
        while (tp > k && (vec[i] - vec[stk[tp]]) * (vec[stk[tp]] - vec[stk[tp - 1]]) >= 0) {
            vis[stk[tp]] = 0;
            tp --;             
        }
        stk[++ tp] = i; 
        vis[i] = 1; 
    }
    vector<Points<>> res; res.clear(); 
    for (int i = 1; i <= tp; i ++) res.push_back(vec[stk[i]]); 
    return res;
}

void solve() {
    vec.clear();
    cin >> n;
    for (int i = 1; i <= n; i ++) {
        LL x, y;
        cin >> x >> y; 
        vec.push_back({x, y});
    }

    vector<Points<>> res; res.clear();
    vector<Points<>> fcon = convex(vec);
    for (auto [x, y] : fcon) rec[{x, y}] = 1;
    for (auto [x, y] : vec) if (!rec[{x, y}]) res.push_back({x, y}); 
    vec = res;
    if (vec.size() == 0) {
        cout << "-1\n"; 
        vec.clear();
        rec.clear();
        return;
    }
    vector<Points<>> scon = convex(vec);
    scon.pop_back();
    LL pid = 0; 
    LL s = 9 * INF;
    for (int i = 0; i < scon.size(); i ++) {
        auto cur = fcon[0] - fcon[1];
        if (abs(cur * (scon[i] - fcon[0])) < s) {
            s = abs(cur * (scon[i] - fcon[0]));
            pid = i;
        }
    }
    // cout << "fcon : \n";
    // for (auto [x, y] : fcon) {
    //     cout << x << " " << y << "\n";
    // } 
    // cout << "scon : \n";
    // for (auto [x, y] : scon) {
    //     cout << x << " " << y << "\n";
    // }

    LL ans = 0;
    s = INF * 9;
    assert(scon.size());
    for (int i = 0; i < fcon.size() - 1; i ++) {
        auto cur = fcon[i] - fcon[i + 1]; 
        while (abs(cur * (scon[pid] - fcon[i])) > abs(cur * (scon[(pid + 1) % scon.size()] - fcon[i]))) 
            pid = (pid + 1) % scon.size();
        // cout << "pid : " << pid << " " << fcon[i].x << ", " << fcon[i].y << " w = " << abs(cur ^ (scon[pid] - fcon[i])) << "\n";
        s = min(s, abs(cur * (scon[pid] - fcon[i])));
        ans += abs(cur * (fcon[i] - fcon[0]));
    }

    // cout << ans << " " << s << "\n";
    cout << ans - s << "\n";
    scon.clear(); fcon.clear(); rec.clear();
}

int main() {
    IO;
    int T;
    cin >> T;
    while (T --) solve(); 
    return 0;
}

这程序好像有点Bug,我给组数据试试?

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3788kb

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: 3832kb

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: 32ms
memory: 3696kb

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: 47ms
memory: 3584kb

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: 83ms
memory: 4760kb

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: 61ms
memory: 4412kb

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: 40ms
memory: 10664kb

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: 130ms
memory: 14712kb

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: 130ms
memory: 14856kb

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: 3568kb

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