Compilare: user.c: In function ‘main’: user.c:89: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:90: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:92: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:95: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:98: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:103: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result