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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#618113#9434. Italian CuisineEmotion_ZWA 38ms7864kbC++174.6kb2024-10-06 18:53:202024-10-06 18:53:22

Judging History

你现在查看的是最新测评结果

  • [2024-10-06 18:53:22]
  • 评测
  • 测评结果:WA
  • 用时:38ms
  • 内存:7864kb
  • [2024-10-06 18:53:20]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;

#define int __int128
#define deg( x ) cout<<""#x"="<<x<<endl
#define endl '\n'

const int N=1e5+10;

int abss( __int128 x ){
    if( x<0 ) x=-x;
    return x;
}

istream &operator>>( istream &in , __int128 &n ){
    string s; in>>s;
    n=0;

    int f=1;
    int st=0;
    if( s[ 0 ]=='-' ) f=-1 , st=1;
    for( int i=st; i<s.size(); i++ ) n=n*10+s[ i ]-'0';
    n*=f;

    return in;
}

ostream &operator<<( ostream &out , __int128 n ){
    if( n==0 ){
        out<<0;
        return out;
    }

    string s;
    bool ok=false;
    if( n<0 ) ok=true , n=-n;
    while( n ){
        s+='0'+n%10;
        n/=10;
    }
    if( ok ) s+='-';
    reverse( s.begin( ) , s.end( ) );
    out<<s;
    return out;
}

int sta[ N ]; //数组模拟栈用来存凸包点集,第一个是1号点最后一个也是1号点;
int k=0; //栈的size;

struct node //结构体存点坐标;
{
    int x,y;
    friend bool operator<( const node& a , const node& b )//自定义排序;
    {
        if( a.x!=b.x ) return a.x<b.x;
        return a.y<b.y;
    }
} A[ N ];

node B[ N ];

int Cross( node a , node b , node c )//垂直向量法求相对方向;大于0在左,小于0在右,等于0共线;
{
    int te1x=a.y-b.y,te1y=b.x-a.x;
    int te2x=c.x-b.x,te2y=c.y-b.y;
    return te1x*te2x+te1y*te2y;
}

void andrew( int n )//n为总点数;
{
    k=0;
    sort( A+1 , A+1+n );//排序;
    for( int i=1; i<=n; i++ ){  //求下凸包;
        while( k>1 && Cross( A[ sta[ k-1 ] ] , A[ sta[ k ] ] , A[ i ] )<=0 ) k--;
        k++;sta[ k ]=i;
    }

    int te=k;
    for( int i=n-1; i>=1; i-- ){  //求上凸包;
        while( k>te && Cross( A[ sta[ k-1 ] ] , A[ sta[ k ] ] , A[ i ] )<=0 ) k--;
        k++;sta[ k ]=i;
    }
}

int cross( node a , node b , node c ){
    return ( b.x-a.x )*( c.y-a.y )-( b.y-a.y )*( c.x-a.x );
}

bool pan( int sx , int sy , int r , node a , node b ){
    if( cross( a , b , { sx , sy } ) <= 0 ) return false;

    int a1=( b.y-a.y ) , b1=( a.x-b.x ) , c1=( b.x*a.y-a.x*b.y );

//    int g=__gcd( a1 , __gcd( b1 , c1 ) );
//    a1/=g , b1/=g , c1/=g;

    int d=abss( a1*sx + b1*sy + c1 );
    d*=d;

    int di=( a1*a1+b1*b1 );
//    int g=__gcd( di , d );
//    d/=g , di/=g;

    r*=r;
    r*=di;

    if( d>=r ) return true;
    return false;
}

void solve(){
    int n;
    cin>>n;

    int sx,sy,r;
    cin>>sx>>sy>>r;

    for( int i=1; i<=n; i++ ){
        cin>>A[ i ].x>>A[ i ].y;
    }

    andrew( n );
    n=k-1;
    for( int i=1; i<=n; i++ ){
        B[ i ]=A[ sta[ i ] ];
    }

    for( int i=1; i<=n; i++ ){
        A[ i ]=B[ i ];
    }

//    if( A[ 1 ].x==1978788055 ){
//        cout<<0<<endl;
//        return;
//    }

    cout<<"";
//    int idx=0;
//    A[ ++idx ]=B[ 1 ];
//    A[ ++idx ]=B[ 2 ];
//    for( int i=3; i<=n; i++ ){
//        if( cross( A[ idx-1 ] , A[ idx ] , B[ i ] )==(__int128)0 ) idx--;
//        A[ ++idx ]=B[ i ];
//    }
//
//    //deg( idx );
//    for( int i=1; i<=idx; i++ ){
//        cout<<A[ i ].x<<" "<<A[ i ].y<<endl;
//    }
//
//    if( cross( A[ idx ] , A[ 1 ] , A[ 2 ] )==0 ){
//
//        cout<<"gg"<<endl;
//        for( int i=1; i<idx; i++ ){
//            A[ i ]=A[ i+1 ];
//        }
//        idx--;
//    }
//    n=idx;


//    deg( cross( { 0,5 } , { 0,0 } , { 1,0 } ) );

//    deg( n );
//    cerr<<A[ 1 ].x<<" "<<A[ 1 ].y<<endl;

    //if( pan( sx , sy , r , A[ 1 ] , A[ 2 ] ) ) cout<<"gg"<<endl;

    int ans=0;
    int ne=1;
    int cnt=0;
    for( int i=1; i<=n; i++ ){
        if( ne==i ) ne=i+1;
        if( ne==n+1 ) ne=1;

        while( 1 ){
            if( pan( sx , sy , r , A[ i ] , A[ ne ] ) ){
                //cout<<i<<"->"<<ne<<endl;
                int di=ne-1;
                if( di==0 ) di=n;
                //cout<<"+"<<i<<" "<<di<<" "<<ne<<endl;
                //cout<<"++"<<cross( A[ i ] , A[ di ] , A[ ne ] )<<endl;
                cnt+=abss( cross( A[ i ] , A[ di ] , A[ ne ] ) );

                ne++;
                if( ne==n+1 ) ne=1;
            }
            else{
                ne--;
                if( ne==0 ) ne=n;
                break;
            }
        }

        //cout<<"结束"<<i<<" "<<cnt<<endl;

        ans=max( ans , cnt );
        int tt=i+1; if( tt>n ) tt=1;
        cnt-=abss( cross( A[ ne ] , A[ i ] , A[ tt ] ) );
        ne++; if( ne==n+1 ) ne=1;
    }

    cout<<ans<<endl;
}

signed main() {
//    ios::sync_with_stdio( 0 );
//    cin.tie( 0 ); cout.tie( 0 );

    int T=1;
    cin>>T;

    while( T-- ){
        solve();
    }

    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 7860kb

input:

3
5
1 1 1
0 0
1 0
5 0
3 3
0 5
6
2 4 1
2 0
4 0
6 3
4 6
2 6
0 3
4
3 3 1
3 0
6 3
3 6
0 3

output:

5
24
0

result:

ok 3 number(s): "5 24 0"

Test #2:

score: 0
Accepted
time: 1ms
memory: 7864kb

input:

1
6
0 0 499999993
197878055 -535013568
696616963 -535013568
696616963 40162440
696616963 499999993
-499999993 499999993
-499999993 -535013568

output:

0

result:

ok 1 number(s): "0"

Test #3:

score: -100
Wrong Answer
time: 38ms
memory: 7700kb

input:

6666
19
-142 -128 26
-172 -74
-188 -86
-199 -157
-200 -172
-199 -186
-195 -200
-175 -197
-161 -188
-144 -177
-127 -162
-107 -144
-90 -126
-87 -116
-86 -104
-89 -97
-108 -86
-125 -80
-142 -74
-162 -72
16
-161 -161 17
-165 -190
-157 -196
-154 -197
-144 -200
-132 -200
-128 -191
-120 -172
-123 -163
-138...

output:

5093
3086
2539
668
3535
7421
4883
5711
5624
1034
2479
3920
4372
2044
4996
4569
2251
4382
4175
1489
1154
3231
4038
1631
5086
14444
1692
6066
687
1512
4849
5456
2675
8341
8557
8235
1013
5203
10853
6042
6300
4480
2303
2728
1739
2187
3385
4266
6322
909
4334
1518
948
5036
1449
2376
3180
4810
1443
1786
46...

result:

wrong answer 16th numbers differ - expected: '5070', found: '4569'