/in/foo.cc: In function 'int main()':
/in/foo.cc:6:27: warning: unused variable 'j' [-Wunused-variable]
     int i,ans=0,sum=0,num,j,k=0;
                           ^
/in/foo.cc:6:29: warning: unused variable 'k' [-Wunused-variable]
     int i,ans=0,sum=0,num,j,k=0;
                             ^
/in/foo.cc: At global scope:
/in/foo.cc:21:1: error: 'Copy' does not name a type
 Copy
 ^~~~