Eroare de compilare: user.c: In function 'main': user.c:15: error: 'c' undeclared (first use in this function) user.c:15: error: (Each undeclared identifier is reported only once user.c:15: error: for each function it appears in.) user.c:15: error: expected ')' before '{' token user.c:29: error: expected ')' before '}' token user.c:29: error: expected expression before '}' token user.c:10: warning: unused variable 'ok' user.c:34:2: warning: no newline at end of file