Compilare: user.c:2: warning: data definition has no type or storage class user.c:2: warning: type defaults to ‘int’ in declaration of ‘a’ user.c: In function ‘main’: user.c:26: warning: passing argument 1 of ‘printf’ makes pointer from integer without a cast /usr/include/bits/stdio2.h:103: note: expected ‘const char * __restrict__’ but argument is of type ‘long long int’ user.c:26: warning: format not a string literal and no format arguments user.c:23: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:24: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:25: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result