6G network

input/code.cpp: In function 'void Test()':
input/code.cpp:162:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  162 |     freopen("temp\\in.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
input/code.cpp: In member function 'void Point::Input()':
input/code.cpp:24:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |         scanf("%lf%lf", &x_, &y_);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=10005;
const double EPS = 1e-8, INF=1e20, PI = acos(-1.0);

inline int Sign(const double& x)
{
    if(fabs(x) < EPS)   return 0;
    if(x < 0)           return -1;
    else                return 1;
}

struct Point
{
    double x_, y_;
    Point(){}
    Point(double x, double y)
    {
        x_ = x;
        y_ = y;
    }
    void Input() {
        scanf("%lf%lf", &x_, &y_);
    }

    bool operator == (const Point& P)const {
        return Sign(x_ - P.x_) == 0 && Sign(y_ - P.y_) == 0;
    }
    bool operator < (const Point& P)const {
        return Sign(x_ - P.x_) == 0? Sign(y_ - P.y_)<0 : x_<P.x_;
    }
    double operator ^ (const Point& P)const {
        return x_*P.y_ - y_*P.x_;
    }
    double operator * (const Point& P)const {
        return x_*P.x_ + y_*P.y_;
    }
    Point operator + (const Point& P)const {
        return Point(x_+P.x_, y_+P.y_);
    }
    Point operator - (const Point& P)const {
        return Point(x_-P.x_, y_-P.y_);
    }
    Point operator * (const double& k)const {
        return Point(x_*k, y_*k);
    }
    Point operator / (const double& k)const {
        return Point(x_/k, y_/k);
    }

    double len() {
        return hypot(x_, y_);
    }
    double dis(Point P) {
        // return hypot(x_ - P.x_, y_ - P.y_);
        double x = x_ - P.x_;
        double y = y_ - P.y_;
        return sqrt(x*x + y*y);
    }
};

struct Line
{
    Point s_, e_;
    Line(){}
    Line(Point s, Point e)
    {
        s_ = s;
        e_ = e;
    }
    Line(Point p, double angle)
    {
        s_ = p;
        if(Sign(angle - PI/2) == 0) {
            e_ = (s_ + Point(0, 1));
        } else {
            e_ = (s_ + Point(1, tan(angle)));
        }
    }
    // 3(O) 2(R) 1(L)
    int Relation(Point p) 
    {
        int c = Sign((p-s_)^(e_-s_));
        if(c < 0)       return 1;
        else if(c > 0)  return 2;
        else            return 3;
    }
    bool OnSeg(Point p) {
        return Sign((p-s_)^(e_-s_)) == 0 && Sign((p-s_)*(p-e_)) <= 0;
    }
};


struct Polygon
{
    int n_;
    Point p_[N];
    Line l_[N];
    void Input(int n)
    {
        n_ = n;
        for(int i=0; i<n_; i++)
            p_[i].Input();
        InitLines();
    }
    void InitLines()
    {
        for(int i=0; i<n_; i++)
            l_[i] = Line(p_[i], p_[(i+1)%n_]);
    }

    double Area()
    {
        double ret = 0;
        for(int i=0; i<n_; i++)
            ret += (p_[i] ^ p_[(i+1)%n_]);
        return fabs(ret)/2;
    }
    // 3(P) 2(E) 1(I) 0(O)
    int Relation(Point p)
    {
        for(int i=0; i<n_; i++)
            if(p_[i] == p)      return 3;
        for(int i=0; i<n_; i++)
            if(l_[i].OnSeg(p))  return 2;
        int cnt = 0;
        for(int i=0; i<n_; i++)
        {
            int j = (i+1)%n_;
            int k = Sign((p-p_[j])^(p_[i]-p_[j]));
            int u = Sign(p_[i].y_ - p.y_);
            int v = Sign(p_[j].y_ - p.y_);
            if(k > 0 && u < 0 && v >= 0) cnt++;
            if(k < 0 && v < 0 && u >= 0) cnt--;
        }
        return cnt != 0;
    }


    void Calc()
    {
        double ans = 0;
        for(int i=0; i<n_; i++)
        {
            double k = INF;
            for(int j=0; j<n_; j++)
            {
                if(i == j)  continue;
                k = min(k, p_[i].dis(p_[j]));
            }
            ans = max(ans, k);
        }
        if(n_ == 1) ans = 0;
        printf("%.20lf", ans);
    }
};


void Test()
{
    freopen("temp\\in.txt", "r", stdin);
}
int main()
{
    // Test();
    int n;
    cin >> n;
    Polygon G;
    G.Input(n);
    G.Calc();

    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: WRONG ANSWER

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: WRONG ANSWER

Test 24

Verdict: ACCEPTED

Test 25

Verdict: WRONG ANSWER

Test 26

Verdict: ACCEPTED

Test 27

Verdict: WRONG ANSWER

Test 28

Verdict: WRONG ANSWER

Test 29

Verdict: ACCEPTED

Test 30

Verdict: WRONG ANSWER

Test 31

Verdict: ACCEPTED

Test 32

Verdict: WRONG ANSWER

Test 33

Verdict: ACCEPTED

Test 34

Verdict: WRONG ANSWER

Test 35

Verdict: ACCEPTED

Test 36

Verdict: ACCEPTED

Test 37

Verdict: ACCEPTED

Test 38

Verdict: WRONG ANSWER

Test 39

Verdict: WRONG ANSWER

Test 40

Verdict: WRONG ANSWER

Test 41

Verdict: WRONG ANSWER

Test 42

Verdict: WRONG ANSWER

Test 43

Verdict: WRONG ANSWER

Test 44

Verdict: WRONG ANSWER

Test 45

Verdict: ACCEPTED

Test 46

Verdict: WRONG ANSWER

Test 47

Verdict: ACCEPTED

Test 48

Verdict: ACCEPTED

Test 49

Verdict: ACCEPTED

Test 50

Verdict: ACCEPTED

Test 51

Verdict: WRONG ANSWER

Test 52

Verdict: WRONG ANSWER

Test 53

Verdict: ACCEPTED

Test 54

Verdict: ACCEPTED

Test 55

Verdict: WRONG ANSWER

Test 56

Verdict: WRONG ANSWER

Test 57

Verdict: ACCEPTED

Test 58

Verdict: WRONG ANSWER

Test 59

Verdict: ACCEPTED

Test 60

Verdict: ACCEPTED

Test 61

Verdict: ACCEPTED

Test 62

Verdict: ACCEPTED

Test 63

Verdict: ACCEPTED

Test 64

Verdict: WRONG ANSWER

Test 65

Verdict: ACCEPTED