Language: C++

#include<iostream>
#include<iomanip>
#include <math.h>
int main(){
	float a, b, c, d, e, f;
	float x, y;
	while (std::cin >> a >> b >> c >> d >> e >> f){
		if (a*d<0){
			d = -d;
			e = -e;
			f = -f;
		}

		x = (c - b*(c - f*a / d) / (b - e*a / d)) / a;
		y = (c - f*a / d) / (b - e*a / d);
		if (x == 0)x = 0;
		if (y == 0)y = 0;
		round(x, 4);
		round(y, 4);
		std::cout<<std::fixed<<std::setprecision(4)  << x << " " << y << std::endl;
	}
	return 0;
	
}

double    round(double src, int n){
	double dst;
	dst = src * pow(10, -n - 1);       
	dst = (double)(int)(dst + 0.5);
	return    dst * pow(10, n + 1);      
}

Compiler output:
a.cc: In function 'int main()':
a.cc:18:22: error: no matching function for call to 'round(float&, int)'
   18 |                 round(x, 4);
      |                 ~~~~~^~~~~~
In file included from /usr/include/c++/14/math.h:36,
                 from a.cc:3:
/usr/include/c++/14/cmath:2699:5: note: candidate: 'template<class _Tp> constexpr typename __gnu_cxx::__enable_if<std::__is_integer<_Tp>::__value, double>::__type std::round(_Tp)'
 2699 |     round(_Tp __x)
      |     ^~~~~
/usr/include/c++/14/cmath:2699:5: note:   candidate expects 1 argument, 2 provided
In file included from /usr/include/features.h:523,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/os_defines.h:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/c++config.h:683,
                 from /usr/include/c++/14/bits/requires_hosted.h:31,
                 from /usr/include/c++/14/iostream:38,
                 from a.cc:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:334:1: note: candidate: 'double round(double)'
  334 | __MATHCALLX (round,, (_Mdouble_ __x), (__const__));
      | ^~~~~~~~~~~
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:334:1: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/cmath:2691:3: note: candidate: 'constexpr long double std::round(long double)'
 2691 |   round(long double __x)
      |   ^~~~~
/usr/include/c++/14/cmath:2691:3: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/cmath:2687:3: note: candidate: 'constexpr float std::round(float)'
 2687 |   round(float __x)
      |   ^~~~~
/usr/include/c++/14/cmath:2687:3: note:   candidate expects 1 argument, 2 provided
a.cc:19:22: error: no matching function for call to 'round(float&, int)'
   19 |                 round(y, 4);
      |                 ~~~~~^~~~~~
/usr/include/c++/14/cmath:2699:5: note: candidate: 'template<class _Tp> constexpr typename __gnu_cxx::__enable_if<std::__is_integer<_Tp>::__value, double>::__type std::round(_Tp)'
 2699 |     round(_Tp __x)
      |     ^~~~~
/usr/include/c++/14/cmath:2699:5: note:   candidate expects 1 argument, 2 provided
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:334:1: note: candidate: 'double round(double)'
  334 | __MATHCALLX (round,, (_Mdouble_ __x), (__const__));
      | ^~~~~~~~~~~
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:334:1: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/cmath:2691:3: note: candidate: 'constexpr long double std::round(long double)'
 2691 |   round(long double __x)
      |   ^~~~~
/usr/include/c++/14/cmath:2691:3: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/cmath:2687:3: note: candidate: 'constexpr float std::round(float)'
 2687 |   round(float __x)
      |   ^~~~~
/usr/include/c++/14/cmath:2687:3: note:   candidate expects 1 argument, 2 provided