Compilare: user.c: In function ‘main’: user.c:56: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:57: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:58: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:62: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:65: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:70: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result