View Compilation Error

0_0_35929018_19244.cpp:4:2: error: stray '#' in program
 =#define ll long long
  ^
0_0_35929018_19244.cpp:4:1: error: expected unqualified-id before '=' token
 =#define ll long long
 ^
0_0_35929018_19244.cpp: In function 'int main()':
0_0_35929018_19244.cpp:13:22: error: 'pi' was not declared in this scope
   double jiao1=sin(2*pi*1.0/n);
                      ^