#include<cstdio>
#include<cstdlib>
#include<ctime>
#include<cmath>
#include<algorithm>
#define pf(x) ((x)*(x)) 
using namespace std;
const int N=1e5+1;
const double eps=1e-7;
struct node{
    double x,y;
    void input(){scanf("%lf%lf",&x,&y);}
}p[N],c;int n,X,Y;double r;
double get_dis(const node &a,const node &b){
    return sqrt(pf(a.x-b.x)+pf(a.y-b.y));
}
node get_focus(const node &a,const node &b,const node &c){
    node t;
    double c1=(a.x*a.x-b.x*b.x+a.y*a.y-b.y*b.y)/2.0;
    double c2=(c.x*c.x-b.x*b.x+c.y*c.y-b.y*b.y)/2.0;
    t.x=(c1*(c.y-b.y)-c2*(a.y-b.y))/((a.x-b.x)*(c.y-b.y)-(c.x-b.x)*(a.y-b.y));
    t.y=(c1*(c.x-b.x)-c2*(a.x-b.x))/((a.y-b.y)*(c.x-b.x)-(c.y-b.y)*(a.x-b.x));
    return t;
}
void work(){
    random_shuffle(p+1,p+n+1);
    c=p[1];r=0;
    for(int i=2;i<=n;i++){
        if(get_dis(p[i],c)+eps>r){
            c=p[i];r=0;
            for(int j=1;j<i;j++){
                if(get_dis(p[j],c)+eps>r){
                    c.x=(p[i].x+p[j].x)/2;
                    c.y=(p[i].y+p[j].y)/2;
                    r=get_dis(c,p[j]);
                    for(int k=1;k<j;k++){
                        if(get_dis(p[k],c)+eps>r){
                            c=get_focus(p[i],p[j],p[k]);
                            r=get_dis(c,p[k]);
                        }
                    }
                }
            }
        }
    }
    printf("(%.1lf,%.1lf).\n%.1lf\n",c.x,c.y,r);
}
int main(){
    srand(time(0));
    while(scanf("%d%d%d",&X,&Y,&n)==3){
        for(int i=1;i<=n;i++) p[i].input();
        work();
    } 
    return 0;
}