Compilare: user.cpp: In function ‘int main()’: user.cpp:52:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f1,"%d",&n); ^ user.cpp:54:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f1,"%lf %lf",&a[i].x,&a[i].y); ^ user.cpp: In function ‘int numara()’: user.cpp:25:41: warning: ‘nr’ may be used uninitialized in this function [-Wmaybe-uninitialized] nr += abs(a[i].y-a[i+1].y)-1; ^