Compilare: user.c: In function ‘main’: user.c:40:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%u%*c%u%*c", &n, &k); ^ user.c:48:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%u%*c", &t); ^ user.c:59:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%u%*c%u%*c", &a, &b); ^ user.c: In function ‘get_lookup’: user.c:172:1: warning: control reaches end of non-void function [-Wreturn-type] } ^