Compilare: user.c: In function ‘print’: user.c:40:5: warning: array subscript has type ‘char’ [-Wchar-subscripts] s[c++]=x%10+'0'; ^ user.c:44:5: warning: array subscript has type ‘char’ [-Wchar-subscripts] ch=s[--c]; ^ user.c: In function ‘nextr’: user.c:13:10: warning: ignoring return value of ‘fread’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, LU, 1, fin); ^