/in/foo.cc: In function 'ZX wang(float*, int)':
/in/foo.cc:14:17: error: found ':' in nested-name-specifier, expected '::'
  for(int i=1;i<n:i++)
                 ^
/in/foo.cc:14:16: error: 'n' is not a class, namespace, or enumeration
  for(int i=1;i<n:i++)
                ^
/in/foo.cc:14:21: error: expected ';' before ')' token
  for(int i=1;i<n:i++)
                     ^