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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#344894#3814. Saint John FestivalKhNURE_KIVI#WA 1ms3764kbC++143.9kb2024-03-05 17:52:492024-03-05 17:52:50

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你现在查看的是最新测评结果

  • [2024-03-05 17:52:50]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:3764kb
  • [2024-03-05 17:52:49]
  • 提交

answer

//#pragma GCC optimize("Ofast", "unroll-loops")
//#pragma GCC target("sse", "sse2", "sse3", "ssse3", "sse4")

#include <bits/stdc++.h>

#define all(a) a.begin(),a.end()
#define len(a) (int)(a.size())
#define mp make_pair
#define pb push_back
#define fir first
#define sec second
#define fi first
#define se second

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
typedef long double ld;

template<typename T>
bool umin(T &a, T b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T>
bool umax(T &a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

#ifdef KIVI
#define DEBUG for (bool _FLAG = true; _FLAG; _FLAG = false)
#define LOG(...) print(#__VA_ARGS__" ::", __VA_ARGS__) << endl
template <class ...Ts> auto &print(Ts ...ts) { return ((cerr << ts << " "), ...); }
#else
#define DEBUG while (false)
#define LOG(...)
#endif

const int max_n = -1, inf = 2000111222;

struct Point
{
    int x,y;
};

ostream& operator<<(ostream& os,const Point& a)
{
    return os<<"{"<<a.x<<","<<a.y<<"}";
}

const bool operator<(const Point& lhs,const Point& rhs)
{
    return mp(lhs.x,lhs.y)<mp(rhs.x,rhs.y);
}

Point operator-(const Point& lhs,const Point& rhs)
{
    return Point{lhs.x-rhs.x,lhs.y-rhs.y};
}

bool cw(const Point& a,const Point& b)
{
    return 1ll * a.x * b.y - 1ll * a.y * b.x < 0;
}

bool ccw(const Point& a,const Point& b)
{
    return 0 < 1ll * a.x * b.y - 1ll * a.y * b.x;
}

bool cw(const Point& a,const Point& b,const Point& c)
{
    return cw(b-a, c-b);
}

bool ccw(const Point& a,const Point& b,const Point& c)
{
    return ccw(b-a, c-b);
}

pair<vector<Point>,vector<Point>> convex_hull(vector<Point> v)
{
    sort(all(v));
    if (len(v)<=2){
        return mp(v,v);
    }
    vector<Point> up,down;
    for (auto p:v){
        if (!ccw(v[0],p,v.back())){
            while (len(up)>=2 && !cw(up[len(up)-2],up.back(),p)){
                up.pop_back();
            }
            up.pb(p);
        }
    }
    for (auto p:v){
        if (!cw(v[0],p,v.back())){
            while (len(down)>=2 && !ccw(down[len(down)-2],down.back(),p)){
                down.pop_back();
            }
            down.pb(p);
        }
    }
    return mp(up,down);
}

int main() {
//    freopen("input.txt", "r", stdin);
//    freopen("output.txt", "w", stdout);

    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin>>n;
    vector<Point> v;
    for (int i=0;i<n;i++){
        int x,y;
        cin>>x>>y;
        v.pb(Point{x,y});
    }
    auto H=convex_hull(v);
    auto up=H.fir;
    auto down=H.sec;

    DEBUG{
        cerr<<"up :: ";
        for (auto i:up){
            cerr<<i<<" ";
        }
        cerr<<"\n";
        cerr<<"down :: ";
        for (auto i:down){
            cerr<<i<<" ";
        }
        cerr<<"\n";
    };

    int ans=0;
    int q;
    cin>>q;
    LOG(q);
    while (q--){
        int x,y;
        cin>>x>>y;
        LOG(x,y);
        bool ok1=0;
        bool ok2=0;

        if (x>=up[0].x && x<=up.back().x){
            int id=upper_bound(all(up),Point{x,+inf})-up.begin()-1;
            id=min(id,len(up)-2);
            const Point& a=up[id];
            const Point& b=up[id+1];

            LOG("for ok1",a,b);

            ok1=!ccw(a,b,Point{x,y});
        }

        if (x>=down[0].x && x<=down.back().x){
            int id=upper_bound(all(down),Point{x,+inf})-down.begin()-1;
            id=min(id,len(down)-2);
            const Point& a=down[id];
            const Point& b=down[id+1];

            LOG("for ok2",a,b);

            ok2=!cw(a,b,Point{x,y});
        }

        if (ok1 && ok2){
            LOG("to answer",x,y);
        }

        ans+=(ok1 && ok2);
    }
    cout<<ans<<"\n";
}

Details

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Test #1:

score: 0
Wrong Answer
time: 1ms
memory: 3764kb

input:

4
1 1
4 1
4 4
1 4
32
0 0
1 0
2 0
3 0
4 0
5 0
0 1
2 1
3 1
5 1
0 2
1 2
2 2
3 2
4 2
5 2
0 3
1 3
2 3
3 3
4 3
5 3
0 4
2 4
3 4
5 4
0 5
1 5
2 5
3 5
4 5
5 5

output:

13

result:

wrong answer 1st lines differ - expected: '12', found: '13'