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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#813940#9869. Horizon Scanningpropane#WA 30ms3876kbC++202.0kb2024-12-14 13:48:562024-12-14 13:48:58

Judging History

This is the latest submission verdict.

  • [2024-12-14 13:48:58]
  • Judged
  • Verdict: WA
  • Time: 30ms
  • Memory: 3876kb
  • [2024-12-14 13:48:56]
  • Submitted

answer

#include<iostream>
#include<cstring>
#include<vector>
#include<algorithm>
#include<cmath>
#include<iomanip>
using namespace std;
using LL = long long;
const long double pi = acos(-1); 

int sign(int x){
    if (x > 0) return 1;
    if (x < 0) return -1;
    return 0;
}

struct Point{
    LL x, y;

    long double angle(){
        return atan2(y, x);
    }

    LL operator^(const Point &t) const {
        return x * t.y - y * t.x;
    }

    LL operator*(const Point &t) const {
        return x * t.x + y * t.y;
    }

    int quad() const {
        if (y < 0) return 1;
        if (y > 0) return 3;
        if (x > 0) return 2;
        return 4;
    };

    bool operator<(const Point &t) const {
        int q1 = quad(), q2 = t.quad();
        if (q1 != q2) return q1 < q2;
        return (*this ^ t) > 0;
    }

    bool operator==(const Point &t) const {
        int q1 = quad(), q2 = t.quad();
        return q1 == q2 and (*this ^ t) == 0;
    }

    long double len(){
        return sqrtl(x * x + y * y);
    }

};

long double a(Point a, Point b){
    long double alpha = acosl(a * b / a.len() / b.len());
    if ((a ^ b) >= 0) return alpha;
    return 2 * pi - alpha;
}

int main(){

#ifdef LOCAL
    freopen("data.in", "r", stdin);
    freopen("data.out", "w", stdout);
#endif

    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(0);
    cout << fixed << setprecision(10);

    int T;
    cin >> T;
    while(T--){
        int n, k;
        cin >> n >> k;
        vector<Point> p(n);
        for(int i = 0; i < n; i++){
            cin >> p[i].x >> p[i].y;
        }
        sort(p.begin(), p.end());
        long double ans = 0;
        for(int i = 0; i < n; i++){
            while(i + 1 < n and p[i] == p[i + 1]) i++;
            if (p[i] == p[(i + k) % n]){
                ans = pi * 2;
            }
            else{
                ans = max(ans, a(p[i], p[(i + k) % n]));
            }
        }
        cout << ans << '\n';
    }

}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3860kb

input:

5
1 1
0 1
8 2
1 0
1 1
0 1
-1 1
-1 0
-1 -1
0 -1
1 -1
4 2
-1 1
0 1
0 2
1 1
4 2
-1000000000 0
-998244353 1
998244353 1
1000000000 0
3 1
0 1
0 2
0 -1

output:

6.2831853072
1.5707963268
5.4977871438
3.1415926546
3.1415926536

result:

ok 5 numbers

Test #2:

score: -100
Wrong Answer
time: 30ms
memory: 3876kb

input:

10000
16 1
-10 -6
-5 -6
-4 9
-2 5
-2 10
1 -7
1 -5
1 6
3 1
4 -9
6 -10
6 -3
6 1
8 -5
8 -4
9 -4
17 4
-9 2
-8 -4
-8 -3
-8 -1
-6 -2
-6 -1
-6 8
-5 -8
-5 10
-4 8
-2 -8
4 -9
4 0
5 -3
8 -5
9 -2
10 10
10 6
-7 2
-4 6
-2 -7
-2 -1
-1 7
1 -9
1 8
3 -4
7 -4
9 -2
14 3
-9 10
-8 -10
-8 -8
-6 -7
-6 -5
-1 -7
-1 -2
0 -1
...

output:

1.6929914975
2.5748634361
4.6527582673
2.7726331074
5.7427658069
4.8576989910
3.4198923126
2.8127999621
6.2831853072
6.2831853072
5.1172807667
6.1467827028
3.8420890235
2.3424967168
3.4633432080
6.2831853072
5.9614347528
3.3247034709
5.2627749281
5.6724593428
1.6738779353
1.1141908549
2.4087775518
6...

result:

wrong answer 314th numbers differ - expected: '3.1415927', found: '2.9996956', error = '0.0451672'