Compilare: main.c: In function 'main': main.c:8:13: warning: passing argument 2 of 'fscanf' from incompatible pointer type [-Wincompatible-pointer-types] fscanf(i, &p); ^ In file included from /usr/include/features.h:367:0, from /usr/include/stdio.h:27, from main.c:1: /usr/include/stdio.h:443:12: note: expected 'const char * restrict' but argument is of type 'long long int *' extern int __REDIRECT (fscanf, (FILE *__restrict __stream, ^ main.c:8:13: warning: format not a string literal and no format arguments [-Wformat-security] fscanf(i, &p); ^~ main.c:17:14: warning: passing argument 2 of 'fprintf' makes pointer from integer without a cast [-Wint-conversion] fprintf(o, r); ^ In file included from /usr/include/stdio.h:936:0, from main.c:1: /usr/include/x86_64-linux-gnu/bits/stdio2.h:95:1: note: expected 'const char * restrict' but argument is of type 'long long int' fprintf (FILE *__restrict __stream, const char *__restrict __fmt, ...) ^~~~~~~ main.c:17:3: warning: format not a string literal and no format arguments [-Wformat-security] fprintf(o, r); ^~~~~~~ main.c:8:3: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(i, &p); ^~~~~~~~~~~~~