Language: C++

#include<stdio.h>
#include<math.h>
#include<string.h>
#include<stdlib.h>
#define sqrt(a) (a)*(a)
#define MAX 1000
#define EPS 1E-6


struct TPoint{    
    double x,y;
}point[1000];

struct TCircle{    
    TPoint centre;
    double r;
}circle;

struct TTriangle{    
    TPoint p0,p1,p2;
}circleedge;

int casenum,pointnum;

inline double 
distance(TPoint p1,TPoint p2){    
    return sqrt(sqr(p1.x-p2.x)+sqr(p1.y-p2.y));
}

inline double
triangleArea(TTriangle t){   
    return fabs(t.p0.x*t.p1.y+t.p1.x*t.p2.y+t.p2.x*t.p0.y - t.p1.x*t.p0.y-t.p2.x*t.p1.y-t.p0.x*t.p2.y)/2;
}

inline TCircle
circumcircle(TTriangle t){    
    TCircle temp;
    double a,b,c,c1,c2;
    double xa,ya,xb,yb,xc,yc;
    a=distance(t.p0,t.p1);
    b=distance(t.p1,t.p2);
    c=distance(t.p2,t.p0);
    temp.r=a*b*c/triangleArea(t)/4;
    xa=t.p0.x;    ya=t.p0.y;
    xb=t.p1.x;    yb=t.p1.y;
    xc=t.p2.x;    yc=t.p2.y;
    c1=(sqr(xa)+sqr(ya)-sqr(xb)-sqr(yb))/2;
    c2=(sqr(xa)+sqr(ya)-sqr(xc)-sqr(yc))/2;
    temp.centre.x=(c1*(ya-yc)-c2*(ya-yb))/((xa-xb)*(ya-yc)-(xa-xc)*(ya-yb));
    temp.centre.y=(c1*(xa-xc)-c2*(xa-xb))/((ya-yb)*(xa-xc)-(ya-yc)*(xa-xb));
    return temp;
}

inline bool
incircle(TPoint p,TCircle c){    
    return distance(p,c.centre)<c.r+EPS? true:false;
}


inline TCircle
minCircle(int pcount,TTriangle ce){    
    TCircle temp;
    memset(&temp,0,sizeof(temp));
    switch(pcount){
    case 0:        
        temp.r=-2;    
        break;
    case 1:        
        temp.centre=ce.p0;    
        break;
    case 2:        
        temp.r=distance(ce.p0,ce.p1)/2;    
        temp.centre.x=(ce.p0.x+ce.p1.x)/2;
        temp.centre.y=(ce.p0.y+ce.p1.y)/2;
        break;
    default:    
        temp=circumcircle(ce);
        break;
    }
    return temp;
}


void 
caculate(int t,int ecount,TTriangle ce){
    int    i;
    circle=minCircle(ecount,ce);
    if(ecount==3) return;
    for(i=0;i<t;i++){
        if(distance(point[i],circle.centre)>circle.r+EPS){    
            switch(ecount){
            case 0: ce.p0=point[i];    break;
            case 1: ce.p1=point[i];    break;
            case 2:    ce.p2=point[i];    break;
            }
            caculate(t-1,ecount+1,ce);
        }
    }
}


void
main(){

    int i;
    TTriangle ce;
        scanf("%d",&pointnum);
        for(i=0;i<pointnum;i++)
            scanf("%lf %lf",&point[i].x,&point[i].y);
        caculate(pointnum,0,ce);
        printf("%.2lf",circle.r);
}


Compiler output:
a.cc:5:2: error: extended character   is not valid in an identifier
    5 | #define sqrt(a) (a)*(a)
      |  ^
a.cc:5:2: error: invalid preprocessing directive #define\U000000a0sqrt
    5 | #define sqrt(a) (a)*(a)
      |  ^~~~~~~~~~~
a.cc:6:2: error: extended character   is not valid in an identifier
    6 | #define MAX 1000
      |  ^
a.cc:6:2: error: extended character   is not valid in an identifier
a.cc:6:2: error: invalid preprocessing directive #define\U000000a0MAX\U000000a01000
    6 | #define MAX 1000
      |  ^~~~~~~~~~~~~~~
a.cc:7:2: error: extended character   is not valid in an identifier
    7 | #define EPS 1E-6
      |  ^
a.cc:7:2: error: extended character   is not valid in an identifier
a.cc:7:2: error: invalid preprocessing directive #define\U000000a0EPS\U000000a01E
    7 | #define EPS 1E-6
      |  ^~~~~~~~~~~~~
a.cc:10:1: error: extended character   is not valid in an identifier
   10 | struct TPoint{    
      | ^
a.cc:10:15: error: extended character   is not valid in an identifier
   10 | struct TPoint{    
      |               ^
a.cc:10:15: error: extended character   is not valid in an identifier
a.cc:10:15: error: extended character   is not valid in an identifier
a.cc:10:15: error: extended character   is not valid in an identifier
a.cc:11:1: error: extended character   is not valid in an identifier
   11 |     double x,y;
      | ^
a.cc:11:1: error: extended character   is not valid in an identifier
a.cc:11:1: error: extended character   is not valid in an identifier
a.cc:11:1: error: extended character   is not valid in an identifier
a.cc:11:1: error: extended character   is not valid in an identifier
a.cc:14:1: error: extended character   is not valid in an identifier
   14 | struct TCircle{    
      | ^
a.cc:14:16: error: extended character   is not valid in an identifier
   14 | struct TCircle{    
      |                ^
a.cc:14:16: error: extended character   is not valid in an identifier
a.cc:14:16: error: extended character   is not valid in an identifier
a.cc:14:16: error: extended character   is not valid in an identifier
a.cc:15:1: error: extended character   is not valid in an identifier
   15 |     TPoint centre;
      | ^
a.cc:15:1: error: extended character   is not valid in an identifier
a.cc:15:1: error: extended character   is not valid in an identifier
a.cc:15:1: error: extended character   is not valid in an identifier
a.cc:15:1: error: extended character   is not valid in an identifier
a.cc:16:1: error: extended character   is not valid in an identifier
   16 |     double r;
      | ^
a.cc:16:1: error: extended character   is not valid in an identifier
a.cc:16:1: error: extended character   is not valid in an identifier
a.cc:16:1: error: extended character   is not valid in an identifier
a.cc:16:1: error: extended character   is not valid in an identifier
a.cc:19:1: error: extended character   is not valid in an identifier
   19 | struct TTriangle{    
      | ^
a.cc:19:18: error: extended character   is not valid in an identifier
   19 | struct TTriangle{    
      |                  ^
a.cc:19:18: error: extended character   is not valid in an identifier
a.cc:19:18: error: extended character   is not valid in an identifier
a.cc:19:18: error: extended character   is not valid in an identifier
a.cc:20:1: error: extended character   is not valid in an identifier
   20 |     TPoint p0,p1,p2;
      | ^
a.cc:20:1: error: extended character   is not valid in an identifier
a.cc:20:1: error: extended character   is not valid in an identifier
a.cc:20:1: error: extended character   is not valid in an identifier
a.cc:20:1: error: extended character   is not valid in an identifier
a.cc:23:1: error: extended character   is not valid in an identifier
   23 | int casenum,pointnum;
      | ^
a.cc:25:1: error: extended character   is not valid in an identifier
   25 | inline double 
      | ^
a.cc:25:1: error: extended character   is not valid in an identifier
a.cc:26:10: error: extended character   is not valid in an identifier
   26 | distance(TPoint p1,TPoint p2){    
      |          ^
a.cc:26:20: error: extended character   is not valid in an identifier
   26 | distance(TPoint p1,TPoint p2){    
      |                    ^
a.cc:26:31: error: extended character   is not valid in an identifier
   26 | distance(TPoint p1,TPoint p2){    
      |                               ^
a.cc:26:31: error: extended character   is not valid in an identifier
a.cc:26:31: error: extended character   is not valid in an identifier
a.cc:26:31: error: extended character   is not valid in an identifier
a.cc:27:1: error: extended character   is not valid in an identifier
   27 |     return sqrt(sqr(p1.x-p2.x)+sqr(p1.y-p2.y));
      | ^
a.cc:27:1: error: extended character   is not valid in an identifier
a.cc:27:1: error: extended character   is not valid in an identifier
a.cc:27:1: error: extended character   is not valid in an identifier
a.cc:27:1: error: extended character   is not valid in an identifier
a.cc:30:1: error: extended character   is not valid in an identifier
   30 | inline double
      | ^
a.cc:31:14: error: extended character   is not valid in an identifier
   31 | triangleArea(TTriangle t){   
      |              ^
a.cc:31:27: error: extended character   is not valid in an identifier
   31 | triangleArea(TTriangle t){   
      |                           ^
a.cc:31:27: error: extended character   is not valid in an identifier
a.cc:31:27: error: extended character   is not valid in an identifier
a.cc:32:1: error: extended character   is not valid in an identifier
   32 |     return fabs(t.p0.x*t.p1.y+t.p1.x*t.p2.y+t.p2.x*t.p0.y - t.p1.x*t.p0.y-t.p2.x*t.p1.y-t.p0.x*t.p2.y)/2;
      | ^
a.cc:32:1: error: extended character   is not valid in an identifier
a.cc:32:1: error: extended character   is not valid in an identifier
a.cc:32:1: error: extended character   is not valid in an identifier
a.cc:32:1: error: extended character   is not valid in an identifier
a.cc:32:57: error: extended character   is not valid in an identifier
   32 |     return fabs(t.p0.x*t.p1.y+t.p1.x*t.p2.y+t.p2.x*t.p0.y - t.p1.x*t.p0.y-t.p2.x*t.p1.y-t.p0.x*t.p2.y)/2;
      |                                                         ^
a.cc:32:60: error: extended character   is not valid in an identifier
   32 |     return fabs(t.p0.x*t.p1.y+t.p1.x*t.p2.y+t.p2.x*t.p0.y - t.p1.x*t.p0.y-t.p2.x*t.p1.y-t.p0.x*t.p2.y)/2;
      |                                                            ^
a.cc:35:1: error: extended character   is not valid in an identifier
   35 | inline TCircle
      | ^
a.cc:36:14: error: extended character   is not valid in an identifier
   36 | circumcircle(TTriangle t){    
      |              ^
a.cc:36:27: error: extended character   is not valid in an identifier
   36 | circumcircle(TTriangle t){    
      |                           ^
a.cc:36:27: error: extended character   is not valid in an identifier
a.cc:36:27: error: extended character   is not valid in an identifier
a.cc:36:27: error: extended character   is not valid in an identifier
a.cc:37:1: error: extended character   is not valid in an identifier
   37 |     TCircle temp;
      | ^
a.cc:37:1: error: extended character   is not valid in an identifier
a.cc:37:1: error: extended character   is not valid in an identifier
a.cc:37:1: error: extended character   is not valid in an identifier
a.cc:37:1: error: extended character   is not valid in an identifier
a.cc:38:1: error: extended character   is not valid in an identifier
   38 |     double a,b,c,c1,c2;
      | ^
a.cc:38:1: error: extended character   is not valid in an identifier
a.cc:38:1: error: extended character   is not valid in an identifier
a.cc:38:1: error: extended character   is not valid in an identifier
a.cc:38:1: error: extended character   is not valid in an identifier
a.cc:39:1: error: extended character   is not valid in an identifier
   39 |     double xa,ya,xb,yb,xc,yc;
      | ^
a.cc:39:1: error: extended character   is not valid in an identifier
a.cc:39:1: error: extended character   is not valid in an identifier
a.cc:39:1: error: extended character   is not valid in an identifier
a.cc:39:1: error: extended character   is not valid in an identifier
a.cc:40:1: error: extended character   is not valid in an identifier
   40 |     a=distance(t.p0,t.p1);
      | ^
a.cc:40:1: error: extended character   is not valid in an identifier
a.cc:40:1: error: extended character   is not valid in an identifier
a.cc:40:1: error: extended character   is not valid in an identifier
a.cc:41:1: error: extended character   is not valid in an identifier
   41 |     b=distance(t.p1,t.p2);
      | ^
a.cc:41:1: error: extended character   is not valid in an identifier
a.cc:41:1: error: extended character   is not valid in an identifier
a.cc:41:1: error: extended character   is not valid in an identifier
a.cc:42:1: error: extended character   is not valid in an identifier
   42 |     c=distance(t.p2,t.p0);
      | ^
a.cc:42:1: error: extended character   is not valid in an identifier
a.cc:42:1: error: extended character   is not valid in an identifier
a.cc:42:1: error: extended character   is not valid in an identifier
a.cc:43:1: error: extended character   is not valid in an identifier
   43 |     temp.r=a*b*c/triangleArea(t)/4;
      | ^
a.cc:43:1: error: extended character   is not valid in an identifier
a.cc:43:1: error: extended character   is not valid in an identifier
a.cc:43:1: error: extended character   is not valid in an identifier
a.cc:44:1: error: extended character   is not valid in an identifier
   44 |     xa=t.p0.x;    ya=t.p0.y;
      | ^
a.cc:44:1: error: extended character   is not valid in an identifier
a.cc:44:1: error: extended character   is not valid in an identifier
a.cc:44:1: error: extended character   is not valid in an identifier
a.cc:44:15: error: extended character   is not valid in an identifier
   44 |     xa=t.p0.x;�