Compilare: user.cpp: In function ‘int main()’: user.cpp:38:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:41:69: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%lf%lf%lf%lf",&s[i].x1,&s[i].y1,&s[i].x2,&s[i].y2); ^ user.cpp:48:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&st[i]); ^