Compilare: user.cpp: In function ‘int main()’: user.cpp:56:18: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:58:35: 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); ^ user.cpp: In function ‘double divide(int, int)’: user.cpp:35:8: warning: ‘mn2’ may be used uninitialized in this function [-Wmaybe-uninitialized] double mn2,mn1; ^