Compilare: user.c: In function ‘main’: user.c:29: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long long int’ user.c:17: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:18: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:19: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result