Language: C++

#include<bits/stdc++.h>
using namespace std;

int main(){
    cout<<fixed<<setprecision(12);
    double a,b,C;
    cin>>a>>b>>C;
    double PI=acos(-1,.0);
    C=C/180.0*PI;
    cout<<a*b*sin(C)/2.0 <<endl;
    double cc=a*a+b*b-2*a*b*cos(C);
    cout<< a+b+sqrt(cc) <<endl;
    cout<<b*sin(C)<<endl;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:8:19: error: no matching function for call to 'acos(int, double)'
    8 |     double PI=acos(-1,.0);
      |               ~~~~^~~~~~~
In file included from /usr/include/c++/14/valarray:605,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166,
                 from a.cc:1:
/usr/include/c++/14/bits/valarray_after.h:447:5: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_UnClos<std::_Acos, std::_ValArray, _Tp>, _Tp> std::acos(const valarray<_Tp>&)'
  447 |     _DEFINE_EXPR_UNARY_FUNCTION(acos, struct std::_Acos)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:447:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/valarray_after.h:447:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_UnClos<std::_Acos, std::_Expr, _Dom>, typename _Dom::value_type> std::acos(const _Expr<_Dom1, typename _Dom1::value_type>&)'
  447 |     _DEFINE_EXPR_UNARY_FUNCTION(acos, struct std::_Acos)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:447:5: note:   candidate expects 1 argument, 2 provided
In file included from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/complex:2213:5: note: candidate: 'template<class _Tp> std::complex<_Tp> std::acos(const complex<_Tp>&)'
 2213 |     acos(const std::complex<_Tp>& __z)
      |     ^~~~
/usr/include/c++/14/complex:2213:5: note:   candidate expects 1 argument, 2 provided
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:114:
/usr/include/c++/14/cmath:105:5: note: candidate: 'template<class _Tp> constexpr typename __gnu_cxx::__enable_if<std::__is_integer<_Tp>::__value, double>::__type std::acos(_Tp)'
  105 |     acos(_Tp __x)
      |     ^~~~
/usr/include/c++/14/cmath:105:5: 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/cassert:43,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:33:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:53:1: note: candidate: 'double acos(double)'
   53 | __MATHCALL_VEC (acos,, (_Mdouble_ __x));
      | ^~~~~~~~~~~~~~
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:53:1: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/cmath:97:3: note: candidate: 'constexpr long double std::acos(long double)'
   97 |   acos(long double __x)
      |   ^~~~
/usr/include/c++/14/cmath:97:3: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/cmath:93:3: note: candidate: 'constexpr float std::acos(float)'
   93 |   acos(float __x)
      |   ^~~~
/usr/include/c++/14/cmath:93:3: note:   candidate expects 1 argument, 2 provided