Submission #881254

#	Time	Username	Problem	Language	Result	Execution time	Memory
881254		Ahmed_Solyman	Odašiljači (COCI20_odasiljaci)	C++14	70 / 70	107 ms	600 KiB

odasiljaci

/*
In the name of Allah
made by: Ahmed_Solyman
*/
#include <bits/stdc++.h>
#include <ext/rope>
 
using namespace std;
using namespace __gnu_cxx;
#pragma GCC optimize("-Ofast")
#pragma GCC optimize("-O1")
//-------------------------------------------------------------//
typedef long long ll;
typedef unsigned long long ull;
#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define PI acos(-1)
#define lb lower_bound
#define ub upper_bound
#define endl '\n'
#define all(v) v.begin(),v.end()
#define allr(v) v.rbegin(),v.rend()
#define sum_to(n) (n*(n+1))/2
#define pb push_back
#define pf push_front
#define fil(arr,x) memset(arr,x,sizeof(arr))
const ll mod=1e9+7;
int dx[8]={0,1,0,-1,1,1,-1,-1};
int dy[8]={1,0,-1,0,1,-1,-1,1};
//-------------------------------------------------------------//
ll lcm(ll a,ll b)
{
    return (max(a,b)/__gcd(a,b))*min(a,b);
}
void person_bool(bool x)
{
    cout<<(x?"YES":"NO")<<endl;
}
struct DSU{
    vector<int>P,sz;
    void init(int n){
        P.resize(n+5);
        sz.assign(n+5,1);
        for(int i=0;i<n+5;i++)P[i]=i;
    }
    int find(int node){
        if(P[node]==node)return node;
        return P[node]=find(P[node]);
    }
    bool unite(int a,int b){
        int p1=find(a);
        int p2=find(b);
        if(p1==p2){
            return 0;
        }
        if(sz[p1]>sz[p2]){
            swap(p1,p2);
        }
        P[p1]=p2;
        sz[p2]+=sz[p1];
        return 1;
    }
}d;
double dist(double a,double b,double c,double d){
    return sqrt(abs(a-c)*abs(a-c)+abs(b-d)*abs(b-d));
}
int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    #ifndef ONLINE_JUDGE
 //   freopen("input.in", "r", stdin);
   // freopen("output.out", "w", stdout);
    #endif
    fast
    int n;cin>>n;
    double a[n+5],b[n+5];
    for(int i=1;i<=n;i++){
        cin>>a[i]>>b[i];
    }
    double l=0,r=1e10;
    double ans=1e10;
    while(r-l>1e-8){
        double mid=(l+r)/2.0;
        d.init(n);
        for(int i=1;i<=n;i++){
            for(int j=i+1;j<=n;j++){
                if(i==j)continue;
                if(dist(a[i],b[i],a[j],b[j])/2.0<mid){
                    d.unite(i, j);
                }
            }
        }
        if(d.sz[d.find(1)]==n){
            r=mid-1e-8;
            ans=mid;
        }
        else{
            l=mid+1e-8;
        }
    }
    cout<<fixed<<setprecision(7)<<ans<<endl;
    return 0;
}

• Subtask 1: 70 / 70