answer.code: In function ‘int main()’:
answer.code:45:13: error: reference to ‘beta’ is ambiguous
   45 |             beta=atan(y/(d-x));
      |             ^~~~
In file included from /usr/include/c++/11/cmath:1935,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:1:
/usr/include/c++/11/bits/specfun.h:343:5: note: candidates are: ‘template<class _Tpa, class _Tpb> typename __gnu_cxx::__promote_2<_Tp, _Up>::__type std::beta(_Tpa, _Tpb)’
  343 |     beta(_Tpa __a, _Tpb __b)
      |     ^~~~
answer.code:4:66: note:                 ‘double beta’
    4 | double l,r,d,R,v,mid,eps=1e-9,ans,temp,pi,x,y,vx,vy,xx,yy,halfpi,beta,maxn;
      |                                                                  ^~~~
answer.code:46:22: error: reference to ‘beta’ is ambiguous
   46 |             vx=2*cos(beta)-1;
      |                      ^~~~
In file included from /usr/include/c++/11/cmath:1935,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:1:
/usr/include/c++/11/bits/specfun.h:343:5: note: candidates are: ‘template<class _Tpa, class _Tpb> typename __gnu_cxx::__promote_2<_Tp, _Up>::__type std::beta(_Tpa, _Tpb)’
  343 |     beta(_Tpa __a, _Tpb __b)
      |     ^~~~
answer.code:4:66: note:                 ‘double beta’
    4 | double l,r,d,R,v,mid,eps=1e-9,ans,temp,pi,x,y,vx,vy,xx,yy,halfpi,beta,maxn;
      |                                                                  ^~~~
answer.code:47:22: error: reference to ‘beta’ is ambiguous
   47 |             vy=2*sin(beta);
      |                      ^~~~
In file included from /usr/include/c++/11/cmath:1935,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:41,
                 from answer.code:1:
/usr/include/c++/11/bits/specfun.h:343:5: note: candidates are: ‘template<class _Tpa, class _Tpb> typename __gnu_cxx::__promote_2<_Tp, _Up>::__type std::beta(_Tpa, _Tpb)’
  343 |     beta(_Tpa __a, _Tpb __b)
      |     ^~~~
answer.code:4:66: note:                 ‘double beta’
    4 | double l,r,d,R,v,mid,eps=1e-9,ans,temp,pi,x,y,vx,vy,xx,yy,halfpi,beta,maxn;
      |                                                                  ^~~~
answer.code:26:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   26 |     scanf("%lld",&T);
      |     ~~~~~^~~~~~~~~~~
answer.code:30:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   30 |         scanf("%lf%lf%lf",&v,&R,&d);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~