Compilare: user.c: In function ‘main’: user.c:73: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:74: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:76: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:78: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:79: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:84: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result