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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
#708296#5426. Drain the Water TankRighttWA 0ms3548kbC++141.9kb2024-11-03 21:12:562024-11-03 21:13:00

Judging History

你现在查看的是最新测评结果

  • [2024-11-03 21:13:00]
  • 评测
  • 测评结果:WA
  • 用时:0ms
  • 内存:3548kb
  • [2024-11-03 21:12:56]
  • 提交

answer

#include <bits/stdc++.h>
#define IOS ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define int long long
using namespace std;

using ll = long long;
using ld = long double;
struct poi{
    ll x,y;
    poi(){
        x=0,y=0;
    }
    poi(ll xx,ll yy){
        x=xx,y=yy;
    }
};
poi operator-(poi a,poi b){return poi(a.x-b.x,a.y-b.y);};
ll cro(poi a,poi b){return a.x*b.y-b.x*a.y;}
//ToLeft测试,判断p是否在ab左边(逆时针),1左,-1右,0在线上
int toleft(poi a,poi b,poi p){
    ll ans=cro((b-a) , (p-b));
    if(ans==0)return 0;
    if(ans>0)return 1;
    return -1;
}

long long get(ll x1, ll y1, ll x2, ll y2){
    return x1 * y2 - x2 * y1;
}

void solve(){
    int n;
    cin>>n;
    ll ans=0;
    vector<poi> p(5*n+5);
    for(int i=0;i<n;i++){
        cin>>p[i].x>>p[i].y;
        p[i+3*n]=p[i+4*n]=p[i+2*n]=p[i+n]=p[i];
    }
    //p.push_back(p[0]);
    for(int i=n*2, jj = n*2+1;i<n*3;i++){
        int j=i,k=i;
        while(p[k-1].y==p[k].y)k--;
        k --;
        while(p[j+1].y==p[j].y)j++;
        j ++;
        if(toleft(p[k-1],p[j+1],p[i])==-1&&p[j+1].y>=p[i].y&&p[k-1].y>=p[i].y)
        ans++;
        //if (k-j-1!=1 && p[i].x>)
        //cout<<i-n<<' '<<j-n<<' '<<k-n<<' '<<p[j+1].y<<' '<<p[k-1].y<<' '<<p[i].y<<endl;
        i=j;

        // while (p[i].y == p[jj].y) jj ++;
        // int pre = i - 1;
        // if (p[i].y < p[pre].y && p[i].y < p[jj].y){
        //     if (p[i].y != p[i + 1].y){
        //         //不在水平线
        //         ans += get(p[i].x-p[pre].x, p[i].y-p[pre].y, p[jj].x-p[i].x, p[jj].y-p[i].y) > 0;
        //     }else{
        //         //水平线
        //         if (p[i+1].x > p[i].x) ans ++;
        //     }
        // }
    }
    cout<<ans;
}

signed main(){
    IOS;
    int t = 1;
//        cin >> t;
    while (t -- ){
        solve();
    }
    return 0;
}

詳細信息

Test #1:

score: 100
Accepted
time: 0ms
memory: 3536kb

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: 0ms
memory: 3544kb

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: -100
Wrong Answer
time: 0ms
memory: 3548kb

input:

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

output:

0

result:

wrong answer 1st numbers differ - expected: '2', found: '0'