Compilare: user.cpp: In function ‘void main2()’: user.cpp:33:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d",&n); ^ user.cpp:36:80: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%lf%lf%lf%lf",&v[i].e[0].x,&v[i].e[0].y,&v[i].e[1].x,&v[i].e[1].y); ^ user.cpp: In function ‘int main()’: user.cpp:114:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d",&t); ^