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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#639446#5426. Drain the Water TankGodwangWA 1ms5772kbC++233.2kb2024-10-13 19:37:532024-10-13 19:37:56

Judging History

你现在查看的是最新测评结果

  • [2024-10-13 19:37:56]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:5772kb
  • [2024-10-13 19:37:53]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#define ll long long 
#define pb push_back
#define rep(i,a,n) for(int i=a;i<=n;i++)
#define per(i,a,n) for(int i=n;i>=a;i--)

const int N=1e5+10;

/////////////////////

int tt;
int n;

struct Point
{
    ll x,y;
    Point()
    {

    }
    Point(ll x,ll y):x(x),y(y){}
    Point operator + (Point B)
    {
        return Point(x+B.x,y+B.y);
    }
    Point operator - (Point B)
    {
        return Point(x-B.x,y-B.y);
    }


};
typedef Point Vector;

ll Cross(Vector A,Vector B)
{
    return A.x*B.y-A.y*B.x;
}
Point p[N],ch[N];


int kaishi;

set<int > se;

/////////////////////

int pre(int u)
{
    if(u==0)
    {
        return n-1;
    }
    return u-1;
}

int nxt(int u)
{
    if(u==n-1)
    {
        return 0;
    }
    return u+1;
}



/////////////////////





/////////////////////



int main()
{
    ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
   // freopen("ain.txt","r",stdin);freopen("aout.txt","w",stdout);

    cin>>n;
    rep(i,0,n-1)
    {
        cin>>p[i].x>>p[i].y;
    }
    kaishi=0;

    while (1)
    {
        int qian=pre(kaishi);
        if(Cross( p[kaishi]-p[qian] , p[1]-p[kaishi])!=0)
        {
            break;
        }
        kaishi=qian;
    }

   
    int dier=1;

    while (1)
    {
        int hou=nxt(dier);
        if(Cross( p[hou]-p[dier] , p[dier]-p[kaishi])!=0)
        {
            break;
        }
        dier=hou;
    }
    
     //


    bool fla=1;
    int a=kaishi,b=dier,c;
    se.insert(a);
    se.insert(b);

    



       //
    //cout<<kaishi<<" "<<dier<<endl;
   // exit(0);

    int temp=0;

    while (1)
    {
        if(fla==0)
        {
            a=b;
        }

        if(fla==0&&a==kaishi)
        {
            break;
        }
        //
        

        

        se.insert(a);
        
        
        fla=0;
        b=nxt(a);
        c=nxt(b);
        //
        //
       // cout<<a<<" "<<b<<" "<<c<<endl;
        //
        
        while (1)
        {
            if(Cross(p[c]-p[b],p[b]-p[a])!=0)
            {
                break;
            }
            b=nxt(b);
            c=nxt(c);
        }


        //
        //
        //cout<<a<<" "<<b<<" "<<c<<endl;
       
    }
    
 

    n=se.size();
   
    //

    int cnt=0;
    for(auto i:se)
    {
        //
        //cout<<i<<endl;
        ch[cnt].x=p[i].x;
        ch[cnt].y=p[i].y;
        cnt++;
    }

    a=0;
    b=1;
    c=2;
    fla=1;
    int ans=0;
    while(1)
    {
        if(a==0&&fla==0)
        {
            break;
        }
        //

        if(p[a].y>p[b].y&&p[b].y<p[c].y)
        {
            if(Cross(ch[b]-ch[a],ch[c]-ch[b])>0)
            {
                ans++;
            }
        }
        if(p[a].y>p[b].y&&p[b].y==p[c].y)
        {
            int d=nxt(c);
           // //
           // cout<<d<<endl;
            if(Cross(ch[c]-ch[b],ch[d]-ch[c])>0)
            {
                ans++;
            }
        }


        a=nxt(a);
        b=nxt(b);
        c=nxt(c);
        fla=0;
    }


    cout<<ans;

    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 5700kb

input:

6
0 0
1 1
2 1
3 0
3 2
0 2

output:

2

result:

ok 1 number(s): "2"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5768kb

input:

8
4 4
0 4
0 2
1 2
2 2
2 0
3 0
4 0

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 5636kb

input:

7
1 0
3 4
0 3
1 2
2 3
1 1
0 2

output:

2

result:

ok 1 number(s): "2"

Test #4:

score: 0
Accepted
time: 1ms
memory: 5704kb

input:

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

output:

2

result:

ok 1 number(s): "2"

Test #5:

score: 0
Accepted
time: 1ms
memory: 5712kb

input:

8
0 0
1 0
3 -1
3 0
1 1
4 1
5 0
3 4

output:

2

result:

ok 1 number(s): "2"

Test #6:

score: 0
Accepted
time: 1ms
memory: 5772kb

input:

5
0 0
170 0
140 30
60 30
0 70

output:

1

result:

ok 1 number(s): "1"

Test #7:

score: 0
Accepted
time: 0ms
memory: 5588kb

input:

5
0 0
170 0
140 30
60 30
0 100

output:

1

result:

ok 1 number(s): "1"

Test #8:

score: 0
Accepted
time: 1ms
memory: 5716kb

input:

5
0 0
1 2
1 5
0 2
0 1

output:

1

result:

ok 1 number(s): "1"

Test #9:

score: 0
Accepted
time: 1ms
memory: 5764kb

input:

3
0 0
100 0
0 100

output:

1

result:

ok 1 number(s): "1"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3724kb

input:

3
200 0
100 100
0 0

output:

1

result:

ok 1 number(s): "1"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3660kb

input:

3
50 50
100 50
100 100

output:

1

result:

ok 1 number(s): "1"

Test #12:

score: 0
Accepted
time: 1ms
memory: 5720kb

input:

3
3 0
0 4
0 0

output:

1

result:

ok 1 number(s): "1"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3600kb

input:

3
10000 10000
-10000 10000
10000 9999

output:

1

result:

ok 1 number(s): "1"

Test #14:

score: 0
Accepted
time: 0ms
memory: 3584kb

input:

3
10000 10000
-10000 10000
10000 9900

output:

1

result:

ok 1 number(s): "1"

Test #15:

score: 0
Accepted
time: 0ms
memory: 3676kb

input:

3
10000 10000
9999 10000
10000 -10000

output:

1

result:

ok 1 number(s): "1"

Test #16:

score: 0
Accepted
time: 1ms
memory: 5604kb

input:

3
0 0
200 0
100 173

output:

1

result:

ok 1 number(s): "1"

Test #17:

score: 0
Accepted
time: 0ms
memory: 3656kb

input:

3
0 0
200 0
100 1

output:

1

result:

ok 1 number(s): "1"

Test #18:

score: 0
Accepted
time: 1ms
memory: 5584kb

input:

3
-10000 -10000
10000 9999
9999 10000

output:

1

result:

ok 1 number(s): "1"

Test #19:

score: 0
Accepted
time: 1ms
memory: 5764kb

input:

4
10 10
20 10
20 20
10 20

output:

1

result:

ok 1 number(s): "1"

Test #20:

score: 0
Accepted
time: 0ms
memory: 5580kb

input:

4
-10000 -10000
10000 -10000
10000 10000
-10000 10000

output:

1

result:

ok 1 number(s): "1"

Test #21:

score: 0
Accepted
time: 0ms
memory: 3596kb

input:

4
100 0
200 100
100 200
0 100

output:

1

result:

ok 1 number(s): "1"

Test #22:

score: 0
Accepted
time: 0ms
memory: 3600kb

input:

4
0 1
100 0
101 100
1 101

output:

1

result:

ok 1 number(s): "1"

Test #23:

score: 0
Accepted
time: 0ms
memory: 3596kb

input:

4
0 0
100 0
100 50
0 50

output:

1

result:

ok 1 number(s): "1"

Test #24:

score: 0
Accepted
time: 1ms
memory: 5760kb

input:

4
0 0
50 0
50 100
0 100

output:

1

result:

ok 1 number(s): "1"

Test #25:

score: 0
Accepted
time: 1ms
memory: 5624kb

input:

4
0 10
10 0
100 90
90 100

output:

1

result:

ok 1 number(s): "1"

Test #26:

score: 0
Accepted
time: 0ms
memory: 3660kb

input:

8
0 100
100 0
250 0
350 100
350 250
250 350
100 350
0 250

output:

1

result:

ok 1 number(s): "1"

Test #27:

score: 0
Accepted
time: 1ms
memory: 5764kb

input:

6
0 50
10 0
70 0
80 10
70 50
50 80

output:

1

result:

ok 1 number(s): "1"

Test #28:

score: 0
Accepted
time: 0ms
memory: 5764kb

input:

4
0 100
0 0
100 0
20 20

output:

1

result:

ok 1 number(s): "1"

Test #29:

score: 0
Accepted
time: 1ms
memory: 5632kb

input:

4
0 100
55 55
100 0
100 100

output:

1

result:

ok 1 number(s): "1"

Test #30:

score: 0
Accepted
time: 1ms
memory: 5716kb

input:

8
0 0
100 0
100 20
40 20
40 40
100 40
100 60
0 60

output:

1

result:

ok 1 number(s): "1"

Test #31:

score: -100
Wrong Answer
time: 0ms
memory: 3584kb

input:

12
0 0
90 0
90 30
40 30
40 40
90 40
90 50
0 50
0 20
50 20
50 10
0 10

output:

2

result:

wrong answer 1st numbers differ - expected: '1', found: '2'