Compilare: user.c: In function ‘main’: user.c:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result user.c:17: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result user.c:18: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result user.c:24: warning: control reaches end of non-void function