Compilare: user.c: In function ‘main’: user.c:47: warning: unused variable ‘k’ user.c:44: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:45: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:48: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:52: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:71: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:73: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result