Compilare: user.c: In function ‘main’: user.c:37: warning: unused variable ‘k’ user.c:34: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:35: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:38: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:42: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:61: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:63: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result