Language: C++

#include <iostream>
#include <algorithm>
#include <complex>
#include <vector>
#include <cmath>
using namespace std;
typedef complex<double> P;

const double eps = 1e-5;
vector<P> ps(3);
double R;

double eval(P p) {
  double sum = 0;
  for(int i = 0; i < ps.size(); ++i)
    sum += abs(R-abs(p-ps[i]));
  return sum;
}

P getBestP(P o, double r) {
  double s = 200;
  double mini = 1e100;
  P bestP;
  double begin = -r;
  double end = r;
  for(int i = 0; i < s; ++i) {
    for(int j = 0; j < s; ++j) {
      P v(begin + j/s*(end-begin), begin + i/s*(end-begin));
      P p = o+v;
      double tmp = eval(p);
      if(tmp < mini) {
	mini = tmp;
	bestP = p;
      }
    }
  }
  return bestP;
}

int main() {
  int Tc;
  cin >> Tc;
  for(int tc = 0; tc < Tc; ++tc) {
    for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
    R = abs(ps[1]-ps[2])/abs(sin(arg(ps[1]-ps[0])-arg(ps[2]-ps[0])))/2.0;
    P res(0,0);
    for(double r = 100.0; r > eps; r *= 0.1) {
      res = getBestP(res, r);
    }
    printf("%.3f %.3f %.3f\n", res.real(), res.imag(), R);
  }
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:44:44: error: no match for 'operator>>' (operand types are 'std::istream' {aka 'std::basic_istream<char>'} and 'double')
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                        ~~~ ^~ ~~~~~~~~~~~~
      |                                        |                |
      |                                        |                double
      |                                        std::istream {aka std::basic_istream<char>}
In file included from /usr/include/c++/14/iostream:42,
                 from a.cc:1:
/usr/include/c++/14/istream:170:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  170 |       operator>>(bool& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:170:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:174:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  174 |       operator>>(short& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:174:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'short int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:177:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  177 |       operator>>(unsigned short& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:177:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'short unsigned int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:181:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  181 |       operator>>(int& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:181:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:184:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  184 |       operator>>(unsigned int& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:184:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'unsigned int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:188:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  188 |       operator>>(long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:188:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'long int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:192:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  192 |       operator>>(unsigned long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:192:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'long unsigned int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:199:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  199 |       operator>>(long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:199:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'long long int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:203:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  203 |       operator>>(unsigned long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:203:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'long long unsigned int&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:219:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(float&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  219 |       operator>>(float& __f)
      |       ^~~~~~~~
/usr/include/c++/14/istream:219:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'float&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:223:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(double&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  223 |       operator>>(double& __f)
      |       ^~~~~~~~
/usr/include/c++/14/istream:223:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'double&' to an rvalue of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:227:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long double&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  227 |       operator>>(long double& __f)
      |       ^~~~~~~~
/usr/include/c++/14/istream:227:7: note:   conversion of argument 1 would be ill-formed:
a.cc:44:57: error: cannot bind non-const lvalue reference of type 'long double&' to a value of type 'double'
   44 |     for(int i = 0; i < ps.size(); ++i) cin >> ps[i].real() >> ps[i].imag();
      |                                               ~~~~~~~~~~^~
/usr/include/c++/14/istream:328:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(void*&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]'
  328 |       operator>>(void*& __p)
      |       ^~~~~~~~
/usr/include/c++/14/istream:328:25: note:   no known conversion for argument 1 from 'double' to 'void*&'
  328 |       operator>>(void*& __p)
      |                  ~~~~~~~^~~
/usr/include/c++/14/istream:122:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__istream_type& (*)(__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]'
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:122:36: note:   no known conversion for argument 1 from 'double' to 'std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&)' {aka 'std::basic_istream<char>& (*)(std::basic_istream<char>&)'}
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |                  ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/istream:126:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__ios_type