Compilare: user.cpp: In function ‘int main()’: user.cpp:40:17: warning: variable ‘D’ set but not used [-Wunused-but-set-variable] int D,x,y; ^ user.cpp:32:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:36:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&a,&b,&c); ^