Compilare: user.c: In function ‘main’: user.c:10:5: warning: passing argument 1 of ‘fscanf’ from incompatible pointer type [enabled by default] fscanf("%d%d%d",&n,&a,&b); ^ In file included from /usr/include/features.h:357:0, from /usr/include/stdio.h:28, from user.c:1: /usr/include/stdio.h:449:12: note: expected ‘struct FILE * restrict’ but argument is of type ‘char *’ extern int __REDIRECT (fscanf, (FILE *__restrict __stream, ^ user.c:10:5: warning: passing argument 2 of ‘fscanf’ from incompatible pointer type [enabled by default] fscanf("%d%d%d",&n,&a,&b); ^ In file included from /usr/include/features.h:357:0, from /usr/include/stdio.h:28, from user.c:1: /usr/include/stdio.h:449:12: note: expected ‘const char * restrict’ but argument is of type ‘int *’ extern int __REDIRECT (fscanf, (FILE *__restrict __stream, ^ user.c:19:5: warning: passing argument 1 of ‘fprintf’ from incompatible pointer type [enabled by default] fprintf("%d\n",k); ^ In file included from /usr/include/stdio.h:934:0, from user.c:1: /usr/include/i386-linux-gnu/bits/stdio2.h:96:1: note: expected ‘struct FILE * restrict’ but argument is of type ‘char *’ fprintf (FILE *__restrict __stream, __const char *__restrict __fmt, ...) ^ user.c:19:5: warning: passing argument 2 of ‘fprintf’ makes pointer from integer without a cast [enabled by default] fprintf("%d\n",k); ^ In file included from /usr/include/stdio.h:934:0, from user.c:1: /usr/include/i386-linux-gnu/bits/stdio2.h:96:1: note: expected ‘const char * restrict’ but argument is of type ‘int’ fprintf (FILE *__restrict __stream, __const char *__restrict __fmt, ...) ^ user.c:10:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf("%d%d%d",&n,&a,&b); ^ user.c:13:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&v[i]); ^