Compilare: user.c: In function ‘main’: user.c:45: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:46: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:50: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:56: 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 user.c:76: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result