Compilare: user.cpp: In function ‘int main()’: user.cpp:53:9: warning: unused variable ‘p’ [-Wunused-variable] { int p; ^ user.cpp: In function ‘void read()’: user.cpp:21:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:23:44: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%lf %lf",&v[i].x,&v[i].y); ^