Eroare de compilare in evaluator: user.c:3: error: conflicting types for 'x' user.c:3: error: previous declaration of 'x' was here user.c: In function 'back': user.c:10: error: 'n2' undeclared (first use in this function) user.c:10: error: (Each undeclared identifier is reported only once user.c:10: error: for each function it appears in.) user.c:16: error: subscripted value is neither array nor pointer user.c:18: error: subscripted value is neither array nor pointer user.c:23: error: subscripted value is neither array nor pointer user.c:31: error: subscripted value is neither array nor pointer user.c:61:2: warning: no newline at end of file