Compilare: user.c: In function ‘main’: user.c:7:28: warning: unused variable ‘cb’ [-Wunused-variable] long long a, b, c, ca, cb; ^~ user.c:7:24: warning: unused variable ‘ca’ [-Wunused-variable] long long a, b, c, ca, cb; ^~ user.c:7:21: warning: unused variable ‘c’ [-Wunused-variable] long long a, b, c, ca, cb; ^ user.c:7:18: warning: unused variable ‘b’ [-Wunused-variable] long long a, b, c, ca, cb; ^ user.c:7:15: warning: unused variable ‘a’ [-Wunused-variable] long long a, b, c, ca, cb; ^ user.c:6:32: warning: variable ‘cn’ set but not used [-Wunused-but-set-variable] int n, *v, i, diff = 0, k, cn; ^~ user.c:6:29: warning: unused variable ‘k’ [-Wunused-variable] int n, *v, i, diff = 0, k, cn; ^ user.c:13:5: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &n); ^~~~~~~~~~~~~~~~~~~~ user.c:18:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &v[i]); ^~~~~~~~~~~~~~~~~~~~~~~