View Compilation Error

0_0_14943423_32170.cpp:4:23: error: stray '@' in program
  if((y%4==0&&y0!=0)||y@0==0)
                       ^
0_0_14943423_32170.cpp: In function 'int fun(int)':
0_0_14943423_32170.cpp:4:14: error: 'y0' was not declared in this scope
  if((y%4==0&&y0!=0)||y@0==0)
              ^
0_0_14943423_32170.cpp:4:24: error: expected ')' before numeric constant
  if((y%4==0&&y0!=0)||y@0==0)
                        ^