Compilare: user.c: In function ‘perm’: user.c:9:13: warning: unused variable ‘sem’ [-Wunused-variable] int i,j,sem; ^ user.c:9:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,sem; ^ user.c: In function ‘main’: user.c:36:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&n); ^