View Compilation Error

0_0_34067956_17634.cpp: In member function 'void fraction::reduce()':
0_0_34067956_17634.cpp:17:13: error: 'x' was not declared in this scope
         a = x / m * sign(y);
             ^
0_0_34067956_17634.cpp:17:26: error: 'y' was not declared in this scope
         a = x / m * sign(y);
                          ^