Compilare: user.c: In function ‘getNumbers’: user.c:20:53: warning: comparison between pointer and integer [enabled by default] while( lin[i] >= '0' && lin[i] <= '9' && lin[i] != NULL ) ^ user.c:25:53: warning: comparison between pointer and integer [enabled by default] while( (lin[i] < '0' || lin[i] > '9') && lin[i] != NULL ) ^ user.c:27:55: warning: comparison between pointer and integer [enabled by default] while( (lin[i] >= '0' && lin[i] <= '9') && lin[i] != NULL ) ^ user.c: In function ‘main’: user.c:34:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen(InFile,"r",stdin); ^ user.c:35:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen(OutFile,"w",stdout); ^ user.c:38:9: warning: ignoring return value of ‘gets’, declared with attribute warn_unused_result [-Wunused-result] gets(lin); ^ user.c:42:13: warning: ignoring return value of ‘gets’, declared with attribute warn_unused_result [-Wunused-result] gets(lin); ^ /tmp/cc1Y6ti3.o: In function `main': user.c:(.text.startup+0x58): warning: the `gets' function is dangerous and should not be used.